0000794105 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:C000007062Member 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member us-gaap:PrepaymentRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:ExtensionRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007062Member 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007062Member 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007062Member 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007062Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007062Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007062Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007062Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007062Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007062Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:C000007060Member 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007060Member 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007060Member 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007060Member 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007060Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007060Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007060Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007060Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007060Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007060Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:C000007057Member 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007057Member 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007057Member 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007057Member 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007057Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007057Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007057Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007057Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007057Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000007057Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:C000007063Member 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member us-gaap:PrepaymentRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:ExtensionRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007063Member 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007063Member 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007063Member 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007063Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007063Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007063Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007063Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007063Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007063Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:C000007061Member 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007061Member 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007061Member 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007061Member 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007061Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007061Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007061Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007061Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007061Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007061Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:C000007058Member 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007058Member 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007058Member 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007058Member 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007058Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007058Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007058Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007058Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007058Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000007058Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:C000209800Member 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000209800Member 2025-12-31 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000209800Member 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000209800Member 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000209800Member 2019-02-07 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000209800Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000209800Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000209800Member oef:AfterTaxesOnDistributionsMember 2019-02-07 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000209800Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000209800Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:C000209800Member oef:AfterTaxesOnDistributionsAndSalesMember 2019-02-07 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUSLongGovCreditFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUSLongGovCreditFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUSLongGovCreditFloatAdjustedIndexMember 2019-02-07 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2019-02-07 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:C000007064Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:C000081425Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member us-gaap:PrepaymentRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:ExtensionRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000007064Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000007064Member 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000007064Member 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000007064Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000007064Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000007064Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000007064Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000007064Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000007064Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000081425Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000081425Member 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000081425Member 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:C000105310Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:C000105311Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105310Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105310Member 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105310Member 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105310Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105310Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105310Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105310Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105310Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105310Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105311Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105311Member 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105311Member 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:C000024520Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:C000105308Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024520Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024520Member 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024520Member 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024520Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024520Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024520Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024520Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024520Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024520Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105308Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105308Member 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105308Member 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:C000024522Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:C000105309Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024522Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024522Member 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024522Member 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024522Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024522Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024522Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024522Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024522Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000024522Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105309Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105309Member 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000105309Member 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSLongGovCreditFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSLongGovCreditFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSLongGovCreditFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:C000170279Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member us-gaap:PrepaymentRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:ExtensionRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:C000170279Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:C000170279Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:C000170279Member 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:C000170279Member 2016-06-24 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:C000170279Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:C000170279Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:C000170279Member oef:AfterTaxesOnDistributionsMember 2016-06-24 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:C000170279Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:C000170279Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:C000170279Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-06-24 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2016-06-24 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:C000046844Member 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member us-gaap:PrepaymentRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:ExtensionRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:ETFShareTradingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:AuthorizedParticipantsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member bondindex:BasedonNAVMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member bondindex:BasedonNAVMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member bondindex:BasedonNAVMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member bondindex:BasedonMarketPriceMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member bondindex:BasedonMarketPriceMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046844Member bondindex:BasedonMarketPriceMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUSAggregateFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:C000046843Member 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:ETFShareTradingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:AuthorizedParticipantsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member bondindex:BasedonNAVMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member bondindex:BasedonNAVMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member bondindex:BasedonNAVMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member bondindex:BasedonMarketPriceMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member bondindex:BasedonMarketPriceMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046843Member bondindex:BasedonMarketPriceMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUS15YearGovCreditFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:C000046841Member 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:ETFShareTradingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:AuthorizedParticipantsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member bondindex:BasedonNAVMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member bondindex:BasedonNAVMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member bondindex:BasedonNAVMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member bondindex:BasedonMarketPriceMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member bondindex:BasedonMarketPriceMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046841Member bondindex:BasedonMarketPriceMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUS510YearGovCreditFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:C000046842Member 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:ETFShareTradingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:AuthorizedParticipantsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member bondindex:BasedonNAVMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member bondindex:BasedonNAVMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member bondindex:BasedonNAVMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member bondindex:BasedonMarketPriceMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member bondindex:BasedonMarketPriceMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000046842Member bondindex:BasedonMarketPriceMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUSLongGovCreditFloatAdjustedIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUSLongGovCreditFloatAdjustedIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUSLongGovCreditFloatAdjustedIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:C000075027Member 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member us-gaap:PrepaymentRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:ExtensionRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000075027Member 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000075027Member 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000075027Member 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000075027Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000075027Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000075027Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000075027Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000075027Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:C000075027Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:C000075028Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member us-gaap:PrepaymentRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:ExtensionRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:IndexInvestingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000075028Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000075028Member 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000075028Member 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000075028Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000075028Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000075028Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000075028Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000075028Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000075028Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:C000054349Member 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:C000054350Member 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:InflationIndexedSecuritiesRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:ActiveManagementRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:DerivativesRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054349Member 2025-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054349Member 2021-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054349Member 2016-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054349Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054349Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054349Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054349Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054349Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054349Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054350Member 2025-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054350Member 2021-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:C000054350Member 2016-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:BloombergUSTreasuryInflationProtectedSecuritiesIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:BloombergUSTreasuryInflationProtectedSecuritiesIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:BloombergUSTreasuryInflationProtectedSecuritiesIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:BloombergUSAggregateBondIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:BloombergUSAggregateBondIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:BloombergUSAggregateBondIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:C000054351Member 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:InflationIndexedSecuritiesRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:ActiveManagementRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:DerivativesRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000054351Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000054351Member 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000054351Member 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000054351Member oef:AfterTaxesOnDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000054351Member oef:AfterTaxesOnDistributionsMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000054351Member oef:AfterTaxesOnDistributionsMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000054351Member oef:AfterTaxesOnDistributionsAndSalesMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000054351Member oef:AfterTaxesOnDistributionsAndSalesMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:C000054351Member oef:AfterTaxesOnDistributionsAndSalesMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSTreasuryInflationProtectedSecuritiesIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSTreasuryInflationProtectedSecuritiesIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSTreasuryInflationProtectedSecuritiesIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSAggregateBondIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSAggregateBondIndexMember 2021-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:BloombergUSAggregateBondIndexMember 2016-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:C000226472Member 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member oef:RiskLoseMoneyMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:GeneralMarketRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:InvestingInBondMarketsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member us-gaap:InterestRateRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:IncomeRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member us-gaap:CreditRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:BondLiquidityRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:CallRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member us-gaap:PrepaymentRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:ExtensionRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:ActiveManagementRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:ManagementOfCertainSimilarFundsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:DerivativesRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:ETFShareTradingRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:AuthorizedParticipantsRiskMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member oef:RiskNotInsuredDepositoryInstitutionMember 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000226472Member 2025-12-31 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000226472Member bondindex:BasedonNAVMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000226472Member bondindex:BasedonNAVMember 2021-04-05 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000226472Member bondindex:BasedonNAVReturnAfterTaxesonDistributionsMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000226472Member bondindex:BasedonNAVReturnAfterTaxesonDistributionsMember 2021-04-05 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000226472Member bondindex:BasedonNAVReturnAfterTaxesonDistributionsandSaleofFundSharesMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000226472Member bondindex:BasedonNAVReturnAfterTaxesonDistributionsandSaleofFundSharesMember 2021-04-05 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000226472Member bondindex:BasedonMarketPriceMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:C000226472Member bondindex:BasedonMarketPriceMember 2021-04-05 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUSTreasuryBellwethers1YearIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUSTreasuryBellwethers1YearIndexMember 2021-04-05 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUSAggregateBondIndexMember 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:BloombergUSAggregateBondIndexMember 2021-04-05 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:C000007062Member 2018-01-01 2018-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:C000007062Member 2019-01-01 2019-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:C000007062Member 2020-01-01 2020-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:C000007062Member 2021-01-01 2021-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:C000007062Member 2022-01-01 2022-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:C000007062Member 2023-01-01 2023-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:C000007062Member 2024-01-01 2024-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002564Member bondindex:C000007062Member 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:C000007063Member 2018-01-01 2018-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:C000007063Member 2019-01-01 2019-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:C000007063Member 2020-01-01 2020-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:C000007063Member 2021-01-01 2021-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:C000007063Member 2022-01-01 2022-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:C000007063Member 2023-01-01 2023-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:C000007063Member 2024-01-01 2024-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002564Member bondindex:C000007063Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:C000007064Member 2018-01-01 2018-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:C000007064Member 2019-01-01 2019-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:C000007064Member 2020-01-01 2020-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:C000007064Member 2021-01-01 2021-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:C000007064Member 2022-01-01 2022-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:C000007064Member 2023-01-01 2023-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:C000007064Member 2024-01-01 2024-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002564Member bondindex:C000007064Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:C000170279Member 2018-01-01 2018-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:C000170279Member 2019-01-01 2019-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:C000170279Member 2020-01-01 2020-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:C000170279Member 2021-01-01 2021-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:C000170279Member 2022-01-01 2022-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:C000170279Member 2023-01-01 2023-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:C000170279Member 2024-01-01 2024-12-31 0000794105 bondindex:InstitutionalSelectProspectusMember bondindex:S000002564Member bondindex:C000170279Member 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:C000046844Member 2018-01-01 2018-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:C000046844Member 2019-01-01 2019-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:C000046844Member 2020-01-01 2020-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:C000046844Member 2021-01-01 2021-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:C000046844Member 2022-01-01 2022-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:C000046844Member 2023-01-01 2023-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:C000046844Member 2024-01-01 2024-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002564Member bondindex:C000046844Member 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:C000226472Member 2022-01-01 2022-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:C000226472Member 2023-01-01 2023-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:C000226472Member 2024-01-01 2024-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000071399Member bondindex:C000226472Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:C000054351Member 2018-01-01 2018-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:C000054351Member 2019-01-01 2019-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:C000054351Member 2020-01-01 2020-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:C000054351Member 2021-01-01 2021-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:C000054351Member 2022-01-01 2022-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:C000054351Member 2023-01-01 2023-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:C000054351Member 2024-01-01 2024-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000019554Member bondindex:C000054351Member 2025-01-01 2025-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:C000054349Member 2018-01-01 2018-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:C000054349Member 2019-01-01 2019-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:C000054349Member 2020-01-01 2020-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:C000054349Member 2021-01-01 2021-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:C000054349Member 2022-01-01 2022-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:C000054349Member 2023-01-01 2023-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:C000054349Member 2024-01-01 2024-12-31 0000794105 bondindex:RetailProspectusMember bondindex:S000019554Member bondindex:C000054349Member 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:C000007060Member 2018-01-01 2018-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:C000007060Member 2019-01-01 2019-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:C000007060Member 2020-01-01 2020-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:C000007060Member 2021-01-01 2021-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:C000007060Member 2022-01-01 2022-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:C000007060Member 2023-01-01 2023-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:C000007060Member 2024-01-01 2024-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002563Member bondindex:C000007060Member 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:C000007061Member 2018-01-01 2018-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:C000007061Member 2019-01-01 2019-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:C000007061Member 2020-01-01 2020-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:C000007061Member 2021-01-01 2021-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:C000007061Member 2022-01-01 2022-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:C000007061Member 2023-01-01 2023-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:C000007061Member 2024-01-01 2024-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002563Member bondindex:C000007061Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:C000105310Member 2018-01-01 2018-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:C000105310Member 2019-01-01 2019-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:C000105310Member 2020-01-01 2020-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:C000105310Member 2021-01-01 2021-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:C000105310Member 2022-01-01 2022-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:C000105310Member 2023-01-01 2023-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:C000105310Member 2024-01-01 2024-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002563Member bondindex:C000105310Member 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:C000046843Member 2018-01-01 2018-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:C000046843Member 2019-01-01 2019-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:C000046843Member 2020-01-01 2020-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:C000046843Member 2021-01-01 2021-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:C000046843Member 2022-01-01 2022-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:C000046843Member 2023-01-01 2023-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:C000046843Member 2024-01-01 2024-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002563Member bondindex:C000046843Member 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:C000075027Member 2018-01-01 2018-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:C000075027Member 2019-01-01 2019-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:C000075027Member 2020-01-01 2020-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:C000075027Member 2021-01-01 2021-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:C000075027Member 2022-01-01 2022-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:C000075027Member 2023-01-01 2023-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:C000075027Member 2024-01-01 2024-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000025158Member bondindex:C000075027Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:C000075028Member 2018-01-01 2018-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:C000075028Member 2019-01-01 2019-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:C000075028Member 2020-01-01 2020-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:C000075028Member 2021-01-01 2021-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:C000075028Member 2022-01-01 2022-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:C000075028Member 2023-01-01 2023-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:C000075028Member 2024-01-01 2024-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000025158Member bondindex:C000075028Member 2025-01-01 2025-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:C000007057Member 2018-01-01 2018-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:C000007057Member 2019-01-01 2019-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:C000007057Member 2020-01-01 2020-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:C000007057Member 2021-01-01 2021-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:C000007057Member 2022-01-01 2022-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:C000007057Member 2023-01-01 2023-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:C000007057Member 2024-01-01 2024-12-31 0000794105 bondindex:InvestorProspectusMember bondindex:S000002561Member bondindex:C000007057Member 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:C000007058Member 2018-01-01 2018-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:C000007058Member 2019-01-01 2019-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:C000007058Member 2020-01-01 2020-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:C000007058Member 2021-01-01 2021-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:C000007058Member 2022-01-01 2022-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:C000007058Member 2023-01-01 2023-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:C000007058Member 2024-01-01 2024-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002561Member bondindex:C000007058Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:C000024520Member 2018-01-01 2018-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:C000024520Member 2019-01-01 2019-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:C000024520Member 2020-01-01 2020-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:C000024520Member 2021-01-01 2021-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:C000024520Member 2022-01-01 2022-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:C000024520Member 2023-01-01 2023-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:C000024520Member 2024-01-01 2024-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002561Member bondindex:C000024520Member 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:C000046841Member 2018-01-01 2018-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:C000046841Member 2019-01-01 2019-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:C000046841Member 2020-01-01 2020-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:C000046841Member 2021-01-01 2021-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:C000046841Member 2022-01-01 2022-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:C000046841Member 2023-01-01 2023-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:C000046841Member 2024-01-01 2024-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002561Member bondindex:C000046841Member 2025-01-01 2025-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:C000209800Member 2020-01-01 2020-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:C000209800Member 2021-01-01 2021-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:C000209800Member 2022-01-01 2022-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:C000209800Member 2023-01-01 2023-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:C000209800Member 2024-01-01 2024-12-31 0000794105 bondindex:AdmiralProspectusMember bondindex:S000002562Member bondindex:C000209800Member 2025-01-01 2025-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:C000024522Member 2018-01-01 2018-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:C000024522Member 2019-01-01 2019-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:C000024522Member 2020-01-01 2020-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:C000024522Member 2021-01-01 2021-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:C000024522Member 2022-01-01 2022-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:C000024522Member 2023-01-01 2023-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:C000024522Member 2024-01-01 2024-12-31 0000794105 bondindex:InstitutionalProspectusMember bondindex:S000002562Member bondindex:C000024522Member 2025-01-01 2025-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:C000046842Member 2018-01-01 2018-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:C000046842Member 2019-01-01 2019-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:C000046842Member 2020-01-01 2020-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:C000046842Member 2021-01-01 2021-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:C000046842Member 2022-01-01 2022-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:C000046842Member 2023-01-01 2023-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:C000046842Member 2024-01-01 2024-12-31 0000794105 bondindex:ETFProspectusMember bondindex:S000002562Member bondindex:C000046842Member 2025-01-01 2025-12-31 pure iso4217:USD 2025-12-31 0000794105 false 485BPOS 0.0002 -0.0013 0.0861 0.0761 -0.0177 -0.1325 0.0560 0.0114 0.0703 -0.0003 0.0871 0.0772 -0.0167 -0.1316 0.0570 0.0124 0.0715 -0.0001 0.0873 0.0774 -0.0165 -0.1315 0.0572 0.0125 0.0717 0.0001 0.0876 0.0776 -0.0163 -0.1313 0.0574 0.0128 0.0718 -0.0004 0.0871 0.0771 -0.0166 -0.1315 0.0570 0.0134 0.0711 -0.0043 0.0556 0.0566 0.0522 -0.0140 0.0818 0.1105 0.0572 -0.1190 0.0385 0.0186 0.0698 -0.0149 0.0806 0.1090 0.0556 -0.1195 0.0365 0.0175 0.0677 0.0127 0.0477 0.0461 -0.0115 -0.0561 0.0479 0.0364 0.0598 0.0135 0.0486 0.0469 -0.0108 -0.0554 0.0487 0.0373 0.0608 0.0137 0.0488 0.0471 -0.0106 -0.0552 0.0488 0.0375 0.0610 0.0134 0.0492 0.0467 -0.0100 -0.0555 0.0491 0.0375 0.0605 -0.0010 0.0862 0.0731 -0.0173 -0.1319 0.0558 0.0124 0.0709 -0.0003 0.0869 0.0738 -0.0167 -0.1312 0.0566 0.0131 0.0717 -0.0025 0.1009 0.0971 -0.0244 -0.1334 0.0599 0.0143 0.0846 -0.0017 0.1018 0.0980 -0.0236 -0.1327 0.0607 0.0151 0.0856 -0.0015 0.1020 0.0982 -0.0234 -0.1325 0.0609 0.0153 0.0858 -0.0009 0.1019 0.0971 -0.0227 -0.1330 0.0616 0.0149 0.0862 0.1623 -0.0266 -0.2722 0.0752 -0.0416 0.0656 -0.0441 0.1912 0.1625 -0.0264 -0.2720 0.0754 -0.0413 0.0658 -0.0446 0.1909 0.1624 -0.0263 -0.2720 0.0753 -0.0409 0.0653 N-1A Vanguard Bond Index Funds 2026-04-28 <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Total Bond Market Index Fund</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Total Bond Market Index Fund (the “Fund”) seeks to track the performance of a broad, market-weighted bond index.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Investor Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 25 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0014 0 0.0001 0.0015 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 15 48 85 192 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">38</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.38 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Aggregate Float Adjusted Index (the “Target Index”). The Target Index measures the performance of a wide spectrum of public, investment-grade, taxable</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds in the United States—including government, corporate, and international dollar-denominated bonds, as well as mortgage-backed and asset-backed securities—all with maturities of more than 1 year. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index and in securities that the advisor determines have substantially identical economic characteristics to the securities that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 8.19 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">fluctuation than the income paid by</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds held by the Fund may be callable. The issuer of a callable bond has the right to “call”</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">(redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price. In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Prepayment Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds are subject to risks associated with prepayment. Prepayment risk for callable bonds is described under </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk</span><span style="font-family:Arial;font-size:9.5pt;">. With respect to mortgage-backed, asset-backed, and similar debt securities, prepayment typically refers to borrowers repaying their debt early (e.g.,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">before the maturity date).</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Prepayment of bonds held by the Fund would result in the Fund losing any price appreciation above the amount repaid (or the bond’s call price,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the case of callable bonds). In addition, because prepayments occur more frequently in low interest rate environments, the Fund likely would be forced to reinvest the proceeds from any prepayments at a lower interest rate than when the prepaid bonds were purchased, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent prepayments and subsequent reinvestment of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Extension Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates, certain bonds held by the Fund may be paid off substantially more slowly than originally anticipated. As a result,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the value of the bonds may fall,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">investments.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target Index regardless of how the Target Index is performing, the Fund’s performance may be lower than it would be if it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in the Target Index, it is subject to the risk that the representative sample of securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of the Target Index. This risk, known as tracking error risk, may be heightened during times of increased market volatility or under other unusual market conditions. The Fund also could be negatively impacted by changes to the Target Index made by the index provider or by errors made by the index provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Investor Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s past </span><span style="font-family:Arial;font-size:9.5pt;">performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on our </span><span style="font-family:Arial;font-size:9.5pt;">website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Investor Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s past </span><span style="font-family:Arial;font-size:9.5pt;">performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Total Bond Market Index Fund Investor Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0666 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0601 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0703 -0.0052 0.0189 0.0540 -0.0170 0.0076 0.0414 -0.0090 0.0096 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">After-tax returns are </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Short-Term Bond Index Fund</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Short-Term Bond Index Fund (the “Fund”) seeks to track the performance of a market-weighted bond index with a short-term dollar-weighted average maturity.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Investor Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 25 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0014 0 0.0001 0.0015 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 15 48 85 192 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">55</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.55 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. 1-5 Year Government/Credit Float Adjusted Index (the “Target Index”),</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which includes all medium and larger issues of U.S. government, investment-grade corporate, and investment-grade international dollar-denominated bonds that have maturities between 1 and 5 years and are publicly issued. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 2.82 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices and</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">interest rates move </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up.</span><span style="font-family:Arial;font-size:9.5pt;"> Bond income also is </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">affected by changes in</span><span style="font-family:Arial;font-size:9.5pt;"> interest rates. Interest rates can rise or fall for a </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">number of reasons, including</span><span style="font-family:Arial;font-size:9.5pt;">, but not limited to,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">central bank monetary policy, </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">could have unpredictable effects on the overall </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the </span><span style="font-family:Arial;font-size:9.5pt;">Fund is impacted by certain </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> During periods of falling interest rates, the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of fluctuation than the income paid by longer-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Index</span><span style="font-family:Arial;font-size:9.5pt;"> regardless of how the Target Index is performing, the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">performance may be lower than it would be if </span><span style="font-family:Arial;font-size:9.5pt;">it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index, it </span><span style="font-family:Arial;font-size:9.5pt;">is subject to the risk that the representative sample of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index</span><span style="font-family:Arial;font-size:9.5pt;">. This risk, known as tracking error risk, may be heightened </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">during times of increased market volatility or under other unusual market conditions. </span><span style="font-family:Arial;font-size:9.5pt;">The Fund also could be negatively impacted by changes to the </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Target Index made by the index provider or by</span><span style="font-family:Arial;font-size:9.5pt;"> errors made by the index </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Investor Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on </span><span style="font-family:Arial;font-size:9.5pt;">our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Investor Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Short-Term Bond Index Fund Investor Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0346 2024-09-30 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0342 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0598 0.0143 0.0202 0.0437 0.0045 0.0116 0.0352 0.0067 0.0117 0.0611 0.0156 0.0217 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">After-tax returns are </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Intermediate-Term Bond Index Fund</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Intermediate-Term Bond Index Fund (the “Fund”) seeks to track the performance of a market-weighted bond index with an intermediate-term dollar-weighted average maturity.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Investor Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 25 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0014 0 0.0001 0.0015 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 15 48 85 192 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">55</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.55 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. 5-10 Year Government/Credit Float Adjusted Index (the “Target Index”),</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which includes all medium and larger issues of U.S. government, investment-grade corporate, and investment-grade international dollar-denominated bonds that have maturities between 5 and 10 years and are publicly issued. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 7.21 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">subject to a higher degree of fluctuation than the income</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">paid by longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Index</span><span style="font-family:Arial;font-size:9.5pt;"> regardless of how the Target Index is performing, the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">performance may be lower than it would be if </span><span style="font-family:Arial;font-size:9.5pt;">it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index, it </span><span style="font-family:Arial;font-size:9.5pt;">is subject to the risk that the representative sample of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index</span><span style="font-family:Arial;font-size:9.5pt;">. This risk, known as tracking error risk, may be heightened </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">during times of increased market volatility or under other unusual market conditions. </span><span style="font-family:Arial;font-size:9.5pt;">The Fund also could be negatively impacted by changes to the </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Target Index made by the index provider or by</span><span style="font-family:Arial;font-size:9.5pt;"> errors made by the index </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Investor Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on </span><span style="font-family:Arial;font-size:9.5pt;">our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Investor Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Intermediate-Term Bond Index Fund Investor Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0685 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0628 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0846 -0.0029 0.0239 0.0672 -0.0154 0.0118 0.0498 -0.0073 0.0133 0.0876 -0.0015 0.0255 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">After-tax returns are </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Total Bond Market Index Fund</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Total Bond Market Index Fund (the “Fund”) seeks to track the performance of a broad, market-weighted bond index.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Admiral Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 25 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0003 0 0.0001 0.0004 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 4 13 23 51 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">38</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.38 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Aggregate Float Adjusted Index (the “Target Index”). The Target Index measures the performance of a wide spectrum of public, investment-grade, taxable</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds in the United States—including government, corporate, and international dollar-denominated bonds, as well as mortgage-backed and asset-backed securities—all with maturities of more than 1 year. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index and in securities that the advisor determines have substantially identical economic characteristics to the securities that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 8.19 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">fluctuation than the income paid by</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds held by the Fund may be callable. The issuer of a callable bond has the right to “call”</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">(redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price. In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Prepayment Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds are subject to risks associated with prepayment. Prepayment risk for callable bonds is described under </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">Call Risk</span><span style="font-family:Arial;font-size:9.5pt;">. With respect to mortgage-backed, asset-backed, and similar debt securities, prepayment typically refers to borrowers repaying their debt early (e.g.,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">before the maturity date).</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Prepayment of bonds held by the Fund would result in the Fund losing any price appreciation above the amount repaid (or the bond’s call price,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the case of callable bonds). In addition, because prepayments occur more frequently in low interest rate environments, the Fund likely would be forced to reinvest the proceeds from any prepayments at a lower interest rate than when the prepaid bonds were purchased, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent prepayments and subsequent reinvestment of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Extension Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates, certain bonds held by the Fund may be paid off substantially more slowly than originally anticipated. As a result,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the value of the bonds may fall,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">investments.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target Index regardless of how the Target Index is performing, the Fund’s performance may be lower than it would be if it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in the Target Index, it is subject to the risk that the representative sample of securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of the Target Index. This risk, known as tracking error risk, may be heightened during times of increased market volatility or under other unusual market conditions. The Fund also could be negatively impacted by changes to the Target Index made by the index provider or by errors made by the index provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Admiral Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Admiral Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s past </span><span style="font-family:Arial;font-size:9.5pt;">performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on our </span><span style="font-family:Arial;font-size:9.5pt;">website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Admiral Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Admiral Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s past </span><span style="font-family:Arial;font-size:9.5pt;">performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Total Bond Market Index Fund Admiral Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0669 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0599 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0715 -0.0042 0.0199 0.0546 -0.0164 0.0082 0.0421 -0.0084 0.0102 0.0721 -0.0037 0.0205 <span style="font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations.</span><span style="font-family:Arial;font-size:9.5pt;">After-tax returns are </span><span style="font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund </span><span style="font-family:Arial;font-size:9.5pt;">shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations.</span> <span style="font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund </span><span style="font-family:Arial;font-size:9.5pt;">shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Short-Term Bond Index Fund</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Short-Term Bond Index Fund (the “Fund”) seeks to track the performance of a market-weighted bond index with a short-term dollar-weighted average maturity.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Admiral Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 25 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0005 0 0.0001 0.0006 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 6 19 34 77 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">55</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.55 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. 1-5 Year Government/Credit Float Adjusted Index (the “Target Index”),</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which includes all medium and larger issues of U.S. government, investment-grade corporate, and investment-grade international dollar-denominated bonds that have maturities between 1 and 5 years and are publicly issued. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 2.82 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices and</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">interest rates move </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up.</span><span style="font-family:Arial;font-size:9.5pt;"> Bond income also is </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">affected by changes in</span><span style="font-family:Arial;font-size:9.5pt;"> interest rates. Interest rates can rise or fall for a </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">number of reasons, including</span><span style="font-family:Arial;font-size:9.5pt;">, but not limited to,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">central bank monetary policy, </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">could have unpredictable effects on the overall </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the </span><span style="font-family:Arial;font-size:9.5pt;">Fund is impacted by certain </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> During periods of falling interest rates, the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of fluctuation than the income paid by longer-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Index</span><span style="font-family:Arial;font-size:9.5pt;"> regardless of how the Target Index is performing, the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">performance may be lower than it would be if </span><span style="font-family:Arial;font-size:9.5pt;">it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index, it </span><span style="font-family:Arial;font-size:9.5pt;">is subject to the risk that the representative sample of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index</span><span style="font-family:Arial;font-size:9.5pt;">. This risk, known as tracking error risk, may be heightened </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">during times of increased market volatility or under other unusual market conditions. </span><span style="font-family:Arial;font-size:9.5pt;">The Fund also could be negatively impacted by changes to the </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Target Index made by the index provider or by</span><span style="font-family:Arial;font-size:9.5pt;"> errors made by the index </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Admiral Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Admiral Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;">past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on our </span><span style="font-family:Arial;font-size:9.5pt;">website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Admiral Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Admiral Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;">past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Short-Term Bond Index Fund Admiral Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0348 2024-09-30 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0340 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0608 0.0152 0.0211 0.0443 0.0050 0.0120 0.0358 0.0072 0.0122 0.0611 0.0156 0.0217 0.0721 -0.0037 0.0205 <span style="font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations.</span><span style="font-family:Arial;font-size:9.5pt;">After-tax returns are </span><span style="font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund </span><span style="font-family:Arial;font-size:9.5pt;">shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations.</span> <span style="font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund </span><span style="font-family:Arial;font-size:9.5pt;">shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Intermediate-Term Bond Index Fund</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Intermediate-Term Bond Index Fund (the “Fund”) seeks to track the performance of a market-weighted bond index with an intermediate-term dollar-weighted average maturity.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Admiral Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 25 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0005 0 0.0001 0.0006 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 6 19 34 77 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">55</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.55 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. 5-10 Year Government/Credit Float Adjusted Index (the “Target Index”),</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which includes all medium and larger issues of U.S. government, investment-grade corporate, and investment-grade international dollar-denominated bonds that have maturities between 5 and 10 years and are publicly issued. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 7.21 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">subject to a higher degree of fluctuation than the income</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">paid by longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Index</span><span style="font-family:Arial;font-size:9.5pt;"> regardless of how the Target Index is performing, the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">performance may be lower than it would be if </span><span style="font-family:Arial;font-size:9.5pt;">it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index, it </span><span style="font-family:Arial;font-size:9.5pt;">is subject to the risk that the representative sample of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index</span><span style="font-family:Arial;font-size:9.5pt;">. This risk, known as tracking error risk, may be heightened </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">during times of increased market volatility or under other unusual market conditions. </span><span style="font-family:Arial;font-size:9.5pt;">The Fund also could be negatively impacted by changes to the </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Target Index made by the index provider or by</span><span style="font-family:Arial;font-size:9.5pt;"> errors made by the index </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Admiral Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Admiral Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;">past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on our </span><span style="font-family:Arial;font-size:9.5pt;">website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Admiral Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Admiral Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;">past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Intermediate-Term Bond Index Fund Admiral Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0687 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0626 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0856 -0.0020 0.0247 0.0678 -0.0149 0.0122 0.0503 -0.0069 0.0138 0.0876 -0.0015 0.0255 0.0721 -0.0037 0.0205 <span style="font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations.</span><span style="font-family:Arial;font-size:9.5pt;">After-tax returns are </span><span style="font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund </span><span style="font-family:Arial;font-size:9.5pt;">shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations.</span> <span style="font-family:Arial;font-size:9.5pt;">not relevant for a shareholder who holds fund </span><span style="font-family:Arial;font-size:9.5pt;">shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Long-Term Bond Index Fund</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Long-Term Bond Index Fund (the “Fund”) seeks to track the performance of a market-weighted bond index with a long-term dollar-weighted average maturity.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Admiral Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0.0050 0 0 25 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0005 0 0.0001 0.0006 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 56 69 84 127 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">24</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.24 <span style="font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Long Government/Credit Float Adjusted Index (the “Target Index”), which includes all medium and larger issues of U.S. government, investment-grade corporate, and investment-grade international dollar-denominated bonds that have maturities of greater than 10 years and are publicly issued. Under normal circumstances,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 22.04 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of fluctuation than the income paid by longer-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Index</span><span style="font-family:Arial;font-size:9.5pt;"> regardless of how the Target Index is performing, the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">performance may be lower than it would be if </span><span style="font-family:Arial;font-size:9.5pt;">it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index, it </span><span style="font-family:Arial;font-size:9.5pt;">is subject to the risk that the representative sample of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index</span><span style="font-family:Arial;font-size:9.5pt;">. This risk, known as tracking error risk, may be heightened </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">during times of increased market volatility or under other unusual market conditions. </span><span style="font-family:Arial;font-size:9.5pt;">The Fund also could be negatively impacted by changes to the </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Target Index made by the index provider or by</span><span style="font-family:Arial;font-size:9.5pt;"> errors made by the index </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Admiral Shares (including annual fund operating expenses but excluding shareholder fees) has varied from one calendar year to another over the periods shown. If applicable shareholder fees were reflected, returns would be less than those shown in the bar chart. The table shows how the average annual total returns of the Admiral Shares (including annual fund operating expenses and any applicable shareholder fees) compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s past performance (before and after </span><span style="font-family:Arial;font-size:9.5pt;">taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated </span><span style="font-family:Arial;font-size:9.5pt;">performance information is available on our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Admiral Shares (including annual fund operating expenses but excluding shareholder fees) has varied from one calendar year to another over the periods shown. If applicable shareholder fees were reflected, returns would be less than those shown in the bar chart. The table shows how the average annual total returns of the Admiral Shares (including annual fund operating expenses and any applicable shareholder fees) compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s past performance (before and after </span><span style="font-family:Arial;font-size:9.5pt;">taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Long-Term Bond Index Fund Admiral Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.1311 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.1227 2022-06-30 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 2019-02-07 0.0602 -0.0499 0.0067 0.0404 -0.0653 -0.0099 0.0354 -0.0429 -0.0008 0.0662 -0.0489 0.0076 0.0721 -0.0037 0.0190 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Total Bond Market Index Fund</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Total Bond Market Index Fund (the “Fund”) seeks to track the performance of a broad, market-weighted bond index.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Institutional Shares or Institutional Plus Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 0 0 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0002 0 0 0.00005 0.0000 0.00025 0.0002 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Examples</span> <span style="font-family:Arial;font-size:9.5pt;">These examples are intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The examples assume that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The examples also assume that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 3 8 14 32 2 6 11 26 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the examples, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">38</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.38 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Aggregate Float Adjusted Index (the “Target Index”). The Target Index measures the performance of a wide spectrum of public, investment-grade, taxable</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds in the United States—including government, corporate, and international dollar-denominated bonds, as well as mortgage-backed and asset-backed securities—all with maturities of more than 1 year. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index and in securities that the advisor determines have substantially identical economic characteristics to the securities that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 8.19 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">fluctuation than the income paid by</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds held by the Fund may be callable. The issuer of a callable bond has the right to “call”</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">(redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price. In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Prepayment Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds are subject to risks associated with prepayment. Prepayment risk for callable bonds is described under </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">Call Risk</span><span style="font-family:Arial;font-size:9.5pt;">. With respect to mortgage-backed, asset-backed, and similar debt securities, prepayment typically refers to borrowers repaying their debt early (e.g.,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">before the maturity date).</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Prepayment of bonds held by the Fund would result in the Fund losing any price appreciation above the amount repaid (or the bond’s call price,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the case of callable bonds). In addition, because prepayments occur more frequently in low interest rate environments, the Fund likely would be forced to reinvest the proceeds from any prepayments at a lower interest rate than when the prepaid bonds were purchased, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent prepayments and subsequent reinvestment of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Extension Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates, certain bonds held by the Fund may be paid off substantially more slowly than originally anticipated. As a result,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the value of the bonds may fall,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">investments.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target Index regardless of how the Target Index is performing, the Fund’s performance may be lower than it would be if it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in the Target Index, it is subject to the risk that the representative sample of securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of the Target Index. This risk, known as tracking error risk, may be heightened during times of increased market volatility or under other unusual market conditions. The Fund also could be negatively impacted by changes to the Target Index made by the index provider or by errors made by the index provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the share classes presented compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on </span><span style="font-family:Arial;font-size:9.5pt;">our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the share classes presented compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Total Bond Market Index Fund Institutional Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0669 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0598 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0717 -0.0041 0.0200 0.0547 -0.0163 0.0083 0.0422 -0.0083 0.0103 0.0717 -0.0040 0.0201 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are shown only for the </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Institutional Shares and may differ for each share class. After-tax returns are </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">not </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">not </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Short-Term Bond Index Fund</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Short-Term Bond Index Fund (the “Fund”) seeks to track the performance of a market-weighted bond index with a short-term dollar-weighted average maturity.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Institutional Shares or Institutional Plus Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 0 0 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0003 0.0002 0 0 0.0000 0.0000 0.0003 0.0002 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Examples</span> <span style="font-family:Arial;font-size:9.5pt;">These examples are intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The examples assume that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The examples also assume that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 3 10 17 39 2 6 11 26 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the examples, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">55</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.55 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. 1-5 Year Government/Credit Float Adjusted Index (the “Target Index”),</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which includes all medium and larger issues of U.S. government, investment-grade corporate, and investment-grade international dollar-denominated bonds that have maturities between 1 and 5 years and are publicly issued. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 2.82 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices and</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> During periods of falling interest rates, the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of fluctuation than the income paid by longer-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target Index regardless of how the Target Index is performing, the Fund’s performance may be lower than it would be if it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in the Target Index, it is subject to the risk that the representative sample of securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of the Target Index. This risk, known as tracking error risk, may be heightened during times of increased market volatility or under other unusual market conditions. The Fund also could be negatively impacted by changes to the Target Index made by the index provider or by errors made by the index provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the share classes presented compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on </span><span style="font-family:Arial;font-size:9.5pt;">our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the share classes presented compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Short-Term Bond Index Fund Institutional Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0348 2024-09-30 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0339 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0610 0.0154 0.0213 0.0444 0.0051 0.0121 0.0359 0.0073 0.0123 0.0611 0.0155 0.0214 0.0611 0.0156 0.0217 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are shown only for the </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Institutional Shares and may differ for each share class. After-tax returns are </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">not </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">not </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Intermediate-Term Bond Index Fund</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Intermediate-Term Bond Index Fund (the “Fund”) seeks to track the performance of a market-weighted bond index with an intermediate-term dollar-weighted average maturity.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Institutional Shares or Institutional Plus Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 0 0 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0003 0.0002 0 0 0.0000 0.0000 0.0003 0.0002 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Examples</span> <span style="font-family:Arial;font-size:9.5pt;">These examples are intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The examples assume that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The examples also assume that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 3 10 17 39 2 6 11 26 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the examples, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">55</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.55 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. 5-10 Year Government/Credit Float Adjusted Index (the “Target Index”),</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which includes all medium and larger issues of U.S. government, investment-grade corporate, and investment-grade international dollar-denominated bonds that have maturities between 5 and 10 years and are publicly issued. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 7.21 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">subject to a higher degree of fluctuation than the income</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">paid by longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target Index regardless of how the Target Index is performing, the Fund’s performance may be lower than it would be if it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in the Target Index, it is subject to the risk that the representative sample of securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of the Target Index. This risk, known as tracking error risk, may be heightened during times of increased market volatility or under other unusual market conditions. The Fund also could be negatively impacted by changes to the Target Index made by the index provider or by errors made by the index provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the share classes presented compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on </span><span style="font-family:Arial;font-size:9.5pt;">our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the share classes presented compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Intermediate-Term Bond Index Fund Institutional Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0687 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0625 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0858 -0.0018 0.0249 0.0679 -0.0148 0.0124 0.0505 -0.0067 0.0139 0.0858 -0.0018 0.0250 0.0876 -0.0015 0.0255 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are shown only for the </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Institutional Shares and may differ for each share class. After-tax returns are </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">not </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">not </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Long-Term Bond Index Fund</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Long-Term Bond Index Fund (the “Fund”) seeks to track the performance of a market-weighted bond index with a long-term dollar-weighted average maturity.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Institutional Shares or Institutional Plus Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0.0050 0.0050 0 0 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0003 0.0002 0 0 0.0000 0.0000 0.0003 0.0002 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Examples</span> <span style="font-family:Arial;font-size:9.5pt;">These examples are intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The examples assume that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The examples also assume that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 53 60 67 88 52 56 61 76 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the examples, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">24</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.24 <span style="font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Long Government/Credit Float Adjusted Index (the “Target Index”), which includes all medium and larger issues of U.S. government, investment-grade corporate, and investment-grade international dollar-denominated bonds that have maturities of greater than 10 years and are publicly issued. Under normal circumstances,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 22.04 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of fluctuation than the income paid by longer-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target Index regardless of how the Target Index is performing, the Fund’s performance may be lower than it would be if it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in the Target Index, it is subject to the risk that the representative sample of securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of the Target Index. This risk, known as tracking error risk, may be heightened during times of increased market volatility or under other unusual market conditions. The Fund also could be negatively impacted by changes to the Target Index made by the index provider or by errors made by the index provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. </span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares (including annual fund operating expenses but excluding shareholder fees) has varied from one calendar year to another over the periods shown. If applicable shareholder fees were reflected, returns would be less than those shown in the bar chart. The table shows how the average annual total returns of the share classes presented (including annual fund operating expenses and any applicable shareholder fees) compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s past performance </span><span style="font-family:Arial;font-size:9.5pt;">(before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares (including annual fund operating expenses but excluding shareholder fees) has varied from one calendar year to another over the periods shown. If applicable shareholder fees were reflected, returns would be less than those shown in the bar chart. The table shows how the average annual total returns of the share classes presented (including annual fund operating expenses and any applicable shareholder fees) compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s past performance </span><span style="font-family:Arial;font-size:9.5pt;">(before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Long-Term Bond Index Fund Institutional Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.1312 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.1227 2022-06-30 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0605 -0.0497 0.0194 0.0406 -0.0652 0.0024 0.0356 -0.0428 0.0084 0.0606 -0.0496 0.0195 0.0662 -0.0489 0.0198 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are shown only for the </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Institutional Shares and may differ for each share class. After-tax returns are </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">not </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">not </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">relevant for a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Fund Summary</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Total Bond Market Index Fund (the “Fund”) seeks to track the performance of a broad, market-weighted bond index.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Institutional Select Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0001 0 0.0000 0.0001 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 1 3 6 13 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">38</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.38 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Aggregate Float Adjusted Index (the “Target Index”). The Target Index measures the performance of a wide spectrum of public, investment-grade, taxable</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds in the United States—including government, corporate, and international dollar-denominated bonds, as well as mortgage-backed and asset-backed securities—all with maturities of more than 1 year. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index and in securities that the advisor determines have substantially identical economic characteristics to the securities that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 8.19 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of fluctuation than the income paid</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">by longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds held by the Fund may be callable. The issuer of a callable bond has the right to “call”</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">(redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price. In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Prepayment Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds are subject to risks associated with prepayment. Prepayment risk for callable bonds is described under </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk</span><span style="font-family:Arial;font-size:9.5pt;">. With respect to mortgage-backed, asset-backed, and similar debt securities, prepayment typically refers to borrowers repaying their debt early (e.g.,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">before the maturity date).</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Prepayment of bonds held by the Fund would result in the Fund losing any price appreciation above the amount repaid (or the bond’s call price,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the case of callable bonds). In addition, because prepayments occur more frequently in low interest rate environments, the Fund likely would be forced to reinvest the proceeds from any prepayments at a lower interest rate than when the prepaid bonds were purchased, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent prepayments and subsequent reinvestment of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Extension Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates, certain bonds held by the Fund may be paid off substantially more slowly than originally anticipated. As a result,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the value of the bonds may fall,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">investments.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target Index regardless of how the Target Index is performing, the Fund’s performance may be lower than it would be if it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in the Target Index, it is subject to the risk that the representative sample of securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of the Target Index. This risk, known as tracking error risk, may be heightened during times of increased market volatility or under other unusual market conditions. The Fund also could be negatively impacted by changes to the Target Index made by the index provider or by errors made by the index provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Select Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Institutional Select Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on </span><span style="font-family:Arial;font-size:9.5pt;">our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Select Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Institutional Select Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Total Bond Market Index Fund Institutional Select Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0670 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0598 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 2016-06-24 0.0718 -0.0038 0.0162 0.0548 -0.0162 0.0043 0.0423 -0.0082 0.0072 0.0721 -0.0037 0.0164 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Total Bond Market ETF</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Total Bond Market ETF, an exchange-traded share class of Vanguard Total Bond Market Index Fund (the “Fund”), seeks to track the performance of a broad, market-weighted bond index.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell ETF Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0002 0 0.0001 0.0003 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 3 10 17 39 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">This example does not include the brokerage commissions that you may pay to buy and sell ETF Shares of the Fund.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">38</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.38 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Aggregate Float Adjusted Index (the “Target Index”). The Target Index measures the performance of a wide spectrum of public, investment-grade, taxable</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds in the United States—including government, corporate, and international dollar-denominated bonds, as well as mortgage-backed and asset-backed securities—all with maturities of more than 1 year. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index and in securities that the advisor determines have substantially identical economic characteristics to the securities that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 8.19 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">fluctuation than the income paid by</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds held by the Fund may be callable. The issuer of a callable bond has the right to “call”</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">(redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price. In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Prepayment Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds are subject to risks associated with prepayment. Prepayment risk for callable bonds is described under </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk</span><span style="font-family:Arial;font-size:9.5pt;">. With respect to mortgage-backed, asset-backed, and similar debt securities, prepayment typically refers to borrowers repaying their debt early (e.g.,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">before the maturity date).</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Prepayment of bonds held by the Fund would result in the Fund losing any price appreciation above the amount repaid (or the bond’s call price,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the case of callable bonds). In addition, because prepayments occur more frequently in low interest rate environments, the Fund likely would be forced to reinvest the proceeds from any prepayments at a lower interest rate than when the prepaid bonds were purchased, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent prepayments and subsequent reinvestment of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Extension Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates, certain bonds held by the Fund may be paid off substantially more slowly than originally anticipated. As a result,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the value of the bonds may fall,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">investments.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target Index regardless of how the Target Index is performing, the Fund’s performance may be lower than it would be if it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in the Target Index, it is subject to the risk that the representative sample of securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of the Target Index. This risk, known as tracking error risk, may be heightened during times of increased market volatility or under other unusual market conditions. The Fund also could be negatively impacted by changes to the Target Index made by the index provider or by errors made by the index provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">ETF Share Trading</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Vanguard ETF Shares (“ETF Shares”) are an exchanged-traded class of shares issued by certain Vanguard funds that represent an interest in the portfolio of securities held by the issuing fund. The Fund’s ETF Shares are listed for trading on Nasdaq and individual investors may only buy and sell them on the secondary market at market prices. Although it is expected that the market price of an ETF Share typically will approximate its net asset value (NAV), there may be times when the market price of an ETF Share and its NAV differ significantly. Disruptions to creation and redemption transactions, the existence of significant market volatility, or potential lack of an active trading market for ETF Shares (including through a trading halt), as well as other factors, may result in ETF Shares trading </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">significantly above (at a premium) or below (at a discount) the Fund’s NAV or the intraday value of the Fund’s holdings.</span><span style="font-family:Arial;font-size:9.5pt;"> Thus, you may pay more or less </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">than NAV when you buy ETF Shares on the secondary market, and you may receive more or less than NAV when you sell those shares.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Authorized Participants</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Only Authorized Participants may engage in creation or redemption transactions directly with the Fund.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The Fund has a limited number of financial institutions that may act as Authorized Participants. The Fund’s Authorized Participants are not obligated to engage in creation or redemption transactions. To the extent that the Fund’s Authorized Participants are unable to or choose not to</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">proceed with creation and/or redemption transactions with respect to the Fund and no other Authorized Participants step forward to engage in creation or redemption transactions with the Fund, the Fund’s ETF Shares may trade at</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">a discount to NAV and possibly face trading halts and/or</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">delisting.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s ETF Shares (based on NAV) has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the ETF Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;">past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on our </span><span style="font-family:Arial;font-size:9.5pt;">website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s ETF Shares (based on NAV) has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the ETF Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;">past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Total Bond Market Index Fund ETF Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0667 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0594 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0711 -0.0040 0.0200 0.0543 -0.0162 0.0083 0.0418 -0.0083 0.0103 0.0708 -0.0044 0.0198 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Short-Term Bond ETF</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Short-Term Bond ETF, an exchanged-traded share class of Vanguard Short-Term Bond Index Fund (the “Fund”), seeks to track the performance of a market-weighted bond index with a short-term dollar-weighted average maturity.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell ETF Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0002 0 0.0001 0.0003 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 3 10 17 39 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">This example does not include the brokerage commissions that you may pay to buy and sell ETF Shares of the Fund.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">55</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.55 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. 1-5 Year Government/Credit Float Adjusted Index (the “Target Index”),</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which includes all medium and larger issues of U.S. government, investment-grade corporate, and investment-grade international dollar-denominated bonds that have maturities between 1 and 5 years and are publicly issued. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 2.82 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices and</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">interest rates move </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up.</span><span style="font-family:Arial;font-size:9.5pt;"> Bond income also is </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">affected by changes in</span><span style="font-family:Arial;font-size:9.5pt;"> interest rates. Interest rates can rise or fall for a </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">number of reasons, including</span><span style="font-family:Arial;font-size:9.5pt;">, but not limited to,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">central bank monetary policy, </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">could have unpredictable effects on the overall </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the </span><span style="font-family:Arial;font-size:9.5pt;">Fund is impacted by certain </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> During periods of falling interest rates, the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of fluctuation than the income paid by longer-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Index</span><span style="font-family:Arial;font-size:9.5pt;"> regardless of how the Target Index is performing, the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">performance may be lower than it would be if </span><span style="font-family:Arial;font-size:9.5pt;">it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index, it </span><span style="font-family:Arial;font-size:9.5pt;">is subject to the risk that the representative sample of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index</span><span style="font-family:Arial;font-size:9.5pt;">. This risk, known as tracking error risk, may be heightened </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">during times of increased market volatility or under other unusual market conditions. </span><span style="font-family:Arial;font-size:9.5pt;">The Fund also could be negatively impacted by changes to the </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Target Index made by the index provider or by</span><span style="font-family:Arial;font-size:9.5pt;"> errors made by the index </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">ETF Share Trading</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Vanguard ETF Shares (“ETF Shares”) are an exchanged-traded class of shares issued by certain Vanguard funds that represent an interest in the portfolio of securities held by the issuing fund. The Fund’s ETF Shares are listed for trading on NYSE Arca and individual investors may only buy and sell them on the secondary market at market prices. Although it is expected that the market price of an ETF Share typically will approximate its net asset value (NAV), there may be times when the market price of an ETF Share and its NAV differ significantly. Disruptions to creation and redemption transactions, the existence of significant market volatility, or potential lack of an active trading market for ETF Shares (including through a trading halt), as well as other factors, may result in ETF Shares trading significantly above (at a premium) or below (at a discount) the Fund’s NAV or the intraday value of the Fund’s holdings. Thus, you may pay more or less than NAV when you buy ETF Shares on the secondary market, and you may receive more or less than NAV when you sell those shares.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Authorized Participants</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Only Authorized Participants may engage in creation or redemption transactions directly with the Fund.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The Fund has a limited number of financial institutions that may act as Authorized Participants. The Fund’s Authorized Participants are not obligated to engage in creation or redemption transactions. To the extent that the Fund’s Authorized Participants are unable to or choose not to</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">proceed with creation and/or redemption transactions with respect to the Fund and no other Authorized Participants step forward to engage in creation or redemption transactions with the Fund, the Fund’s ETF Shares may trade at</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">a discount to NAV and possibly face trading halts and/or</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">delisting.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s ETF Shares (based on NAV) has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the ETF Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on </span><span style="font-family:Arial;font-size:9.5pt;">our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s ETF Shares (based on NAV) has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the ETF Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Short-Term Bond Index Fund ETF Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0350 2024-09-30 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0342 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0605 0.0154 0.0212 0.0440 0.0051 0.0121 0.0356 0.0073 0.0123 0.0599 0.0153 0.0211 0.0611 0.0156 0.0217 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Intermediate-Term Bond ETF</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Intermediate-Term Bond ETF, an exchange-traded share class of Vanguard Intermediate-Term Bond Index Fund (the “Fund”), seeks to track the performance of a market-weighted bond index with an intermediate-term dollar-weighted average maturity.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell ETF Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0002 0 0.0001 0.0003 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 3 10 17 39 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">This example does not include the brokerage commissions that you may pay to buy and sell ETF Shares of the Fund.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">55</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.55 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. 5-10 Year Government/Credit Float Adjusted Index (the “Target Index”),</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which includes all medium and larger issues of U.S. government, investment-grade corporate, and investment-grade international dollar-denominated bonds that have maturities between 5 and 10 years and are publicly issued. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 7.21 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">subject to a higher degree of fluctuation than the income</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">paid by longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Index</span><span style="font-family:Arial;font-size:9.5pt;"> regardless of how the Target Index is performing, the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">performance may be lower than it would be if </span><span style="font-family:Arial;font-size:9.5pt;">it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index, it </span><span style="font-family:Arial;font-size:9.5pt;">is subject to the risk that the representative sample of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index</span><span style="font-family:Arial;font-size:9.5pt;">. This risk, known as tracking error risk, may be heightened </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">during times of increased market volatility or under other unusual market conditions. </span><span style="font-family:Arial;font-size:9.5pt;">The Fund also could be negatively impacted by changes to the </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Target Index made by the index provider or by</span><span style="font-family:Arial;font-size:9.5pt;"> errors made by the index </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">ETF Share Trading</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Vanguard ETF Shares (“ETF Shares”) are an exchanged-traded class of shares issued by certain Vanguard funds that represent an interest in the portfolio of securities held by the issuing fund. The Fund’s ETF Shares are listed for trading on NYSE Arca and individual investors may only buy and sell them on the secondary market at market prices. Although it is expected that the market price of an ETF Share typically will approximate its net asset value (NAV), there may be times when the market price of an ETF Share and its NAV differ significantly. Disruptions to creation and redemption transactions, the existence of significant market volatility, or potential lack of an active trading market for ETF Shares (including through a trading halt), as well as other factors, may result in ETF Shares trading significantly above (at a premium) or below (at a discount) the Fund’s NAV or the intraday value of the Fund’s holdings. Thus, you may pay more or less than NAV when you buy ETF Shares on the secondary market, and you may receive more or less than NAV when you sell those shares.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Authorized Participants</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Only Authorized Participants may engage in creation or redemption transactions directly with the Fund.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The Fund has a limited number of financial institutions that may act as Authorized Participants. The Fund’s Authorized Participants are not obligated to engage in creation or redemption transactions. To the extent that the Fund’s Authorized Participants are unable to or choose not to</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">proceed with creation and/or redemption transactions with respect to the Fund and no other Authorized Participants step forward to engage in creation or redemption transactions with the Fund, the Fund’s ETF Shares may trade at</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">a discount to NAV and possibly face trading halts and/or</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">delisting.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s ETF Shares (based on NAV) has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the ETF Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on </span><span style="font-family:Arial;font-size:9.5pt;">our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s ETF Shares (based on NAV) has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the ETF Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Intermediate-Term Bond Index Fund ETF Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0687 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0631 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0862 -0.0017 0.0249 0.0685 -0.0146 0.0124 0.0507 -0.0066 0.0139 0.0852 -0.0020 0.0247 0.0876 -0.0015 0.0255 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Vanguard Long-Term Bond ETF</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Long-Term Bond ETF, an exchange-traded share class of Vanguard Long-Term Bond Index Fund (the “Fund”), seeks to track the performance of a market-weighted bond index with a long-term dollar-weighted average maturity.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell ETF Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0002 0 0.0001 0.0003 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 3 10 17 39 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">This example does not include the brokerage commissions that you may pay to buy and sell ETF Shares of the Fund.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">24</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.24 <span style="font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Long Government/Credit Float Adjusted Index (the “Target Index”), which includes all medium and larger issues of U.S. government, investment-grade corporate, and investment-grade international dollar-denominated bonds that have maturities of greater than 10 years and are publicly issued. Under normal circumstances,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 22.04 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of fluctuation than the income paid by longer-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Index</span><span style="font-family:Arial;font-size:9.5pt;"> regardless of how the Target Index is performing, the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">performance may be lower than it would be if </span><span style="font-family:Arial;font-size:9.5pt;">it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index, it </span><span style="font-family:Arial;font-size:9.5pt;">is subject to the risk that the representative sample of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the </span><span style="font-family:Arial;font-size:9.5pt;">Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">the Target Index</span><span style="font-family:Arial;font-size:9.5pt;">. This risk, known as tracking error risk, may be heightened </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">during times of increased market volatility or under other unusual market conditions. </span><span style="font-family:Arial;font-size:9.5pt;">The Fund also could be negatively impacted by changes to the </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Target Index made by the index provider or by</span><span style="font-family:Arial;font-size:9.5pt;"> errors made by the index </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">ETF Share Trading</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Vanguard ETF Shares (“ETF Shares”) are an exchanged-traded class of shares issued by certain Vanguard funds that represent an interest in the portfolio of securities held by the issuing fund. The Fund’s ETF Shares are listed for trading on NYSE Arca and individual investors may only buy and sell them on the secondary market at market prices. Although it is expected that the market price of an ETF Share typically will approximate its net asset value (NAV), there may be times when the market price of an ETF Share and its NAV differ significantly. Disruptions to creation and redemption transactions, the existence of significant market volatility, or potential lack of an active trading market for ETF Shares (including through a trading halt), as well as other factors, may result in ETF Shares trading significantly above (at a premium) or below (at a discount) the Fund’s NAV or the intraday value of the Fund’s holdings. Thus, you may pay more or less than NAV when you buy ETF Shares on the secondary market, and you may receive more or less than NAV when you sell those shares.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Authorized Participants</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Only Authorized Participants may engage in creation or redemption transactions directly with the Fund.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The Fund has a limited number of financial institutions that may act as Authorized Participants. The Fund’s Authorized Participants are not obligated to engage in creation or redemption transactions. To the extent that the Fund’s Authorized Participants are unable to or choose not to</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">proceed with creation and/or redemption transactions with respect to the Fund and no other Authorized Participants step forward to engage in creation or redemption transactions with the Fund, the Fund’s ETF Shares may trade at</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">a discount to NAV and possibly face trading halts and/or</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">delisting.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s ETF Shares (based on NAV) has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the ETF Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on </span><span style="font-family:Arial;font-size:9.5pt;">our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s ETF Shares (based on NAV) has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the ETF Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Long-Term Bond Index Fund ETF Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.1311 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.1225 2022-06-30 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0653 -0.0488 0.0198 0.0453 -0.0643 0.0029 0.0384 -0.0421 0.0087 0.0643 -0.0490 0.0197 0.0662 -0.0489 0.0198 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Fund Summary</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Total Bond Market II Index Fund (the “Fund”) seeks to track the performance of a broad, market-weighted bond index.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Investor Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 25 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0008 0 0.0001 0.0009 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 9 29 51 115 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">107</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 1.07 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Aggregate Float Adjusted Index (the “Target Index”). The Target Index measures the performance of a wide spectrum of public, investment-grade, taxable</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds in the United States—including government, corporate, and international dollar-denominated bonds, as well as mortgage-backed and asset-backed securities—all with maturities of more than 1 year. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index and in securities that the advisor determines have substantially identical economic characteristics to the securities that make up the Target Index. </span><span style="font-family:Arial;font-size:9.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 8.2</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">fluctuation than the income paid by</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds held by the Fund may be callable. The issuer of a callable bond has the right to “call”</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">(redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price. In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Prepayment Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds are subject to risks associated with prepayment. Prepayment risk for callable bonds is described under </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk</span><span style="font-family:Arial;font-size:9.5pt;">. With respect to mortgage-backed, asset-backed, and similar debt securities, prepayment typically refers to borrowers repaying their debt early (e.g.,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">before the maturity date).</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Prepayment of bonds held by the Fund would result in the Fund losing any price appreciation above the amount repaid (or the bond’s call price,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the case of callable bonds). In addition, because prepayments occur more frequently in low interest rate environments, the Fund likely would be forced to reinvest the proceeds from any prepayments at a lower interest rate than when the prepaid bonds were purchased, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent prepayments and subsequent reinvestment of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Extension Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates, certain bonds held by the Fund may be paid off substantially more slowly than originally anticipated. As a result,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the value of the bonds may fall,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">investments.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target Index regardless of how the Target Index is performing, the Fund’s performance may be lower than it would be if it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in the Target Index, it is subject to the risk that the representative sample of securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of the Target Index. This risk, known as tracking error risk, may be heightened during times of increased market volatility or under other unusual market conditions. The Fund also could be negatively impacted by changes to the Target Index made by the index provider or by errors made by the index provider. Any gains, losses, or costs associated with or resulting from an error made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Investor Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s past </span><span style="font-family:Arial;font-size:9.5pt;">performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on our </span><span style="font-family:Arial;font-size:9.5pt;">website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Investor Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s past </span><span style="font-family:Arial;font-size:9.5pt;">performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Total Bond Market II Index Fund Investor Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0664 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0601 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0709 -0.0047 0.0190 0.0540 -0.0167 0.0073 0.0417 -0.0087 0.0096 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Fund Summary</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Total Bond Market II Index Fund (the “Fund”) seeks to track the performance of a broad, market-weighted bond index.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Institutional Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0002 0 0.0000 0.0002 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 2 6 11 26 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">107</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 1.07 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an indexing investment approach designed to track the performance of the Bloomberg U.S. Aggregate Float Adjusted Index (the “Target Index”). The Target Index measures the performance of a wide spectrum of public, investment-grade, taxable</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds in the United States—including government, corporate, and international dollar-denominated bonds, as well as mortgage-backed and asset-backed securities—all with maturities of more than 1 year. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in the bonds that make up the Target Index and in securities that the advisor determines have substantially identical economic characteristics to the securities that make up the Target Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests by sampling the Target Index, meaning that it holds a range of securities that, in the aggregate, approximates the full Target Index in terms of key risk factors and other characteristics. The Fund maintains a dollar-weighted average maturity consistent with that of the Target Index. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 8.2 years.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bond prices overall may decline,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">which could result in a decline in the Fund’s value.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of longer-term bonds</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">fluctuation than the income paid by</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds held by the Fund may be callable. The issuer of a callable bond has the right to “call”</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">(redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price. In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Prepayment Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Certain bonds are subject to risks associated with prepayment. Prepayment risk for callable bonds is described under </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk</span><span style="font-family:Arial;font-size:9.5pt;">. With respect to mortgage-backed, asset-backed, and similar debt securities, prepayment typically refers to borrowers repaying their debt early (e.g.,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">before the maturity date).</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Prepayment of bonds held by the Fund would result in the Fund losing any price appreciation above the amount repaid (or the bond’s call price,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the case of callable bonds). In addition, because prepayments occur more frequently in low interest rate environments, the Fund likely would be forced to reinvest the proceeds from any prepayments at a lower interest rate than when the prepaid bonds were purchased, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent prepayments and subsequent reinvestment of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Extension Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates, certain bonds held by the Fund may be paid off substantially more slowly than originally anticipated. As a result,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the value of the bonds may fall,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">investments.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Index Investing</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund is subject to risks associated with index investing. Because the Fund generally seeks to track the performance of the Target Index regardless of how the Target Index is performing, the Fund’s performance may be lower than it would be if it were actively managed. Additionally,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">because the Fund does not hold all of the securities included in the Target Index, it is subject to the risk that the representative sample of securities selected by the advisor will, in the aggregate, vary from the investment profile of the full Target Index. The performance of the Fund’s investments,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the aggregate,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may not match the investment performance of the Target Index. This risk, known as tracking error risk, may be heightened during times of increased market volatility or under other unusual market conditions. The Fund also could be negatively impacted by changes to the Target Index made by the index provider or by errors made by the index provider. Any gains, losses, or costs associated with or resulting from an error </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">made by the index provider will generally be borne by the Fund and, as a result, the Fund’s shareholders.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Institutional Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;">past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on our </span><span style="font-family:Arial;font-size:9.5pt;">website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Institutional Shares compare with those of a broad-based securities market</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">index.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;">past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Total Bond Market II Index Fund Institutional Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0666 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0599 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0717 -0.0040 0.0197 0.0544 -0.0163 0.0077 0.0422 -0.0083 0.0100 0.0721 -0.0037 0.0205 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Fund Summary</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Inflation-Protected Securities Fund (the “Fund”) seeks to provide inflation protection and income consistent with investment in inflation-indexed securities.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Investor Shares or Admiral Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 0 0 0 0 25 25 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0019 0.0009 0 0 0.0001 0.0001 0.0020 0.0010 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Examples</span> <span style="font-family:Arial;font-size:9.5pt;">These examples are intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The examples assume that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The examples also assume that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 20 64 113 255 10 32 56 128 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the examples, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">60</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.60 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an active management approach, investing mainly in investment-grade, inflation-indexed bonds. Under normal circumstances, the Fund invests at least 80% of its net assets,</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">plus the amount of any borrowings for investment purposes, in inflation-indexed bonds issued by the U.S. government, its agencies and instrumentalities, and corporations. At a minimum, all bonds purchased by the Fund are rated investment-grade by an independent bond rating agency or, if unrated, are determined by the Fund’s advisor to be of comparable quality. The Fund may invest in bonds of any maturity but generally expects to maintain a dollar-weighted average maturity in the range of 7 to 20 years.</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;">The Fund invests primarily in U.S. Treasury inflation-protected securities (commonly known as “TIPS”), which are a type of inflation-indexed security. Inflation-indexed securities provide interest and principal payments that are adjusted over time to reflect a rise (inflation) or a drop (deflation) in the general price level for goods and services. The periodic adjustment of TIPS is tied to the Consumer Price Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;">The Fund may invest in derivatives such as fixed income futures contracts, fixed income options (including options on swaps), interest rate swaps, total return swaps, credit default swaps, or other derivatives.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up.</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons,</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">including,</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">but not limited to,</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">central bank monetary policy, inflationary or deflationary pressures,</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and changes in general market and economic conditions. Changing interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">including,</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity,</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and/or average duration of its bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> During periods of rising interest rates, bond prices overall may decline, which could result in a decline in the Fund’s value. The prices of longer-term bonds are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> During periods of falling interest rates, the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of fluctuation than the income paid by longer-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Inflation-Indexed Securities.</span><span style="font-family:Arial;font-size:9.5pt;"> Because they are adjusted for inflation, TIPS and other inflation-indexed securities typically have lower yields than conventional bonds. As a result of its investment in such securities, the Fund’s income distributions are likely to fluctuate considerably more than the income distributions of a conventional bond fund. In fact, under certain conditions, the Fund may not have income to distribute at all. Although the prices of inflation-indexed securities are not meaningfully affected by changes in “nominal”</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">(stated) interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">their prices may decline when</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">“real” (adjusted for inflation) interest rates rise, and vice versa.</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of inflation-indexed securities also are subject to decline if prices throughout the U.S.</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">economy decline over time (a period of deflation), which could result in a loss to the Fund and/or cause the Fund’s performance to lag that of conventional bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">funds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Active Management.</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The Fund is actively managed.</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The advisor’s security selection and/or strategy execution could cause the Fund to underperform relevant securities markets or other funds with a similar investment objective.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Derivatives</span><span style="font-family:Arial;font-size:9.5pt;">. Investing in derivatives</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may present risks different from, and/or greater than, those associated with investing directly in stocks, bonds, or other types of investments.</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Derivatives could expose the Fund to increased volatility and/or significant loss. Certain derivatives have an inherent leverage component,</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">providing the Fund exposure to a sizable position in an underlying asset with a relatively small upfront investment at the time the Fund enters into the derivatives position. For these derivatives,</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">an adverse change in the value or price of the underlying asset could result in a loss substantially greater than the amount invested in the derivative itself. Some derivatives require the Fund to enter into a contract with a counterparty. If the counterparty is unable or unwilling to fulfill its contractual obligation, the Fund may experience a loss. A liquid market may not always exist for the Fund’s derivatives positions. The Fund may be unable to sell or otherwise exit its derivatives position at desired times or prices, which could also result in a loss to the Fund. Some derivatives, particularly OTC derivatives, can be complex and often are valued subjectively. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Fund.</span> <br/><span style="font-family:Arial;font-size:9.5pt;">Derivatives may not perform as intended, which may result in losses to the Fund. For example, derivatives used for hedging or as a substitute for a portfolio instrument may not provide the expected benefits, particularly during adverse market conditions. The use of derivatives is also subject to legal risk, which includes the risk of loss resulting from insufficient or unenforceable contractual documentation, insufficient capacity or authority of the Fund’s counterparty, and operational risk, which includes documentation or settlement issues, system failures, inadequate controls, and human</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">error.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the share classes presented compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on </span><span style="font-family:Arial;font-size:9.5pt;">our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Investor Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the share classes presented compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Inflation-Protected Securities Fund Investor Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0460 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0601 2022-06-30 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0677 0.0092 0.0288 0.0481 -0.0115 0.0135 0.0400 -0.0019 0.0155 0.0687 0.0103 0.0298 0.0701 0.0112 0.0309 0.0730 -0.0036 0.0201 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are shown only for the Investor </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Shares and may differ for each share class. After-tax returns are </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">not relevant for </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">not relevant for </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">a shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:13pt;font-weight:bold;">Fund Summary</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Inflation-Protected Securities Fund (the “Fund”) seeks to provide inflation protection and income consistent with investment in inflation-indexed securities.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell Institutional Shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0006 0 0.0001 0.0007 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 7 23 40 90 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">60</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.60 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an active management approach, investing mainly in investment-grade, inflation-indexed bonds. Under normal circumstances, the Fund invests at least 80% of its net assets,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">plus the amount of any borrowings for investment purposes, in inflation-indexed bonds issued by the U.S. government, its agencies and instrumentalities, and corporations. At a minimum, all bonds purchased by the Fund are rated investment-grade by an independent bond rating agency or, if unrated, are determined by the Fund’s advisor to be of comparable quality. The Fund may invest in bonds of any maturity but generally expects to maintain a dollar-weighted average maturity in the range of 7 to 20 years.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund invests primarily in U.S. Treasury inflation-protected securities (commonly known as “TIPS”), which are a type of inflation-indexed security. Inflation-indexed securities provide interest and principal payments that are adjusted over time to reflect a rise (inflation) or a drop (deflation) in the general price level for goods and services. The periodic adjustment of TIPS is tied to the Consumer Price Index.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund may invest in derivatives such as fixed income futures contracts, fixed income options (including options on swaps), interest rate swaps, total return swaps, credit default swaps, or other derivatives.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">including,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">but not limited to,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">central bank monetary policy, inflationary or deflationary pressures,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and changes in general market and economic conditions. Changing interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">including,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and/or average duration of its bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> During periods of rising interest rates, bond prices overall may decline, which could result in a decline in the Fund’s value. The prices of longer-term bonds are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> During periods of falling interest rates, the Fund’s income may decline. The income paid by shorter-term bonds is subject to a higher degree of fluctuation than the income paid by longer-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund. In addition, negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced. There may be limited trading in the secondary market for certain debt securities, which could make them more difficult to value or sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Inflation-Indexed Securities.</span><span style="font-family:Arial;font-size:9.5pt;"> Because they are adjusted for inflation, TIPS and other inflation-indexed securities typically have lower yields than conventional bonds. As a result of its investment in such securities, the Fund’s income distributions are likely to fluctuate considerably more than the income distributions of a conventional bond fund. In fact, under certain </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">conditions, the Fund may not have </span><span style="font-family:Arial;font-size:9.5pt;">income to distribute at all. Although the </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">prices of inflation-indexed securities are not meaningfully affected by </span><span style="font-family:Arial;font-size:9.5pt;">changes </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">in </span><span style="font-family:Arial;font-size:9.5pt;">“nominal”</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">(stated) interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">their prices may decline when</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">“real” </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">(adjusted for inflation) interest rates rise</span><span style="font-family:Arial;font-size:9.5pt;">, and vice versa.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The prices of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">inflation</span><span style="font-family:Arial;font-size:9.5pt;">-indexed securities also are subject to decline if prices throughout the </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">U</span><span style="font-family:Arial;font-size:9.5pt;">.S.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">economy decline over time (a period of deflation), which could result in a </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">loss to the Fund and/or cause</span><span style="font-family:Arial;font-size:9.5pt;"> the Fund’s performance to lag that of </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">conventional bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">funds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Active Management.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The Fund is actively managed.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The advisor’s security selection and/or strategy execution could cause the Fund to underperform relevant securities markets or other funds with a similar investment objective.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Derivatives</span><span style="font-family:Arial;font-size:9.5pt;">. Investing in derivatives</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">may present risks different from, and/or greater than, those associated with investing directly in stocks, bonds, or other types of investments.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Derivatives could expose the Fund to increased volatility and/or significant loss. Certain derivatives have an inherent leverage component,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">providing the Fund exposure to a sizable position in an underlying asset with a relatively small upfront investment at the time the Fund enters into the derivatives position. For these derivatives,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">an adverse change in the value or price of the underlying asset could result in a loss substantially greater than the amount invested in the derivative itself. Some derivatives require the Fund to enter into a contract with a counterparty. If the counterparty is unable or unwilling to fulfill its contractual obligation, the Fund may experience a loss. A liquid market may not always exist for the Fund’s derivatives positions. The Fund may be unable to sell or otherwise exit its derivatives position at desired times or prices, which could also result in a loss to the Fund. Some derivatives, particularly OTC derivatives, can be complex and often are valued subjectively. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Fund.</span> <br/><span style="font-family:Arial;font-size:9.5pt;">Derivatives may not perform as intended, which may result in losses to the Fund. For example, derivatives used for hedging or as a substitute for a portfolio instrument may not provide the expected benefits, particularly during adverse market conditions. The use of derivatives is also subject to legal risk, which includes the risk of loss resulting from insufficient or unenforceable contractual documentation, insufficient capacity or authority of the Fund’s counterparty, and operational risk, which includes documentation or settlement issues, system failures, inadequate controls, and human</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">error.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Institutional Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span><span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on </span><span style="font-family:Arial;font-size:9.5pt;">our website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s Institutional Shares has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Institutional Shares compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund.</span> <span style="font-family:Arial;font-size:9.5pt;"> Keep in mind that </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Inflation-Protected Securities Fund Institutional Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0464 2023-12-31 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0598 2022-06-30 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 0.0698 0.0106 0.0301 0.0496 -0.0107 0.0143 0.0412 -0.0011 0.0163 0.0701 0.0112 0.0309 0.0730 -0.0036 0.0201 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="font-family:Arial;font-size:13pt;font-weight:bold;">Fund Summary</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span> <span style="font-family:Arial;font-size:9.5pt;">Vanguard Ultra-Short Bond ETF (the “Fund”) seeks to provide current income while maintaining limited price volatility.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Fees and Expenses</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">The following tables describe the fees and expenses you may pay if you buy, hold, and sell shares of the Fund. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.</span> <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Fees paid directly from your investment)</span> 0 0 <span style="color:#000000;font-family:Arial;font-size:8.5pt;font-weight:bold;">Annual Fund Operating Expenses</span> <br/><span style="color:#000000;font-family:Arial;font-size:8.5pt;">(Expenses that you pay each year as a percentage of the value of your investment)</span> 0.0009 0 0.0001 0.0010 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Example</span> <span style="font-family:Arial;font-size:9.5pt;">This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The example assumes that you invest $10,000 in the Fund for</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.3pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5%</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.3pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">return each year</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.3pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and that the Fund’s operating expenses remain the</span><span style="font-family:Arial;font-size:9.5pt;line-height:10.3pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">same.</span> 10 32 56 128 <span style="font-family:Arial;font-size:9.5pt;">This example does not include the brokerage commissions that you may pay to buy and sell shares of the Fund.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Portfolio Turnover</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was </span><span style="font-family:Arial;font-size:9.5pt;">65</span><span style="font-family:Arial;font-size:9.5pt;">% of the average value of its portfolio.</span> 0.65 <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategies</span> <span style="font-family:Arial;font-size:9.5pt;">The Fund employs an active management approach, investing in a diversified portfolio of high-quality and, to a lesser extent, medium-quality bonds. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in bonds. For purposes of the 80% policy, bonds include fixed income securities such as corporate bonds; U.S.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Treasury obligations and other U.S. government and agency securities; and asset-backed,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">mortgage-backed,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">and mortgage-related securities.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The Fund expects to maintain a dollar-weighted average maturity of 0 to 2 years.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund purchases investment-grade bonds. Investment-grade bonds include those rated the equivalent of A3 or better (high-quality) and those rated the equivalent of Baa1, Baa2, or Baa3 (medium-quality) by Moody’s or another independent rating agency, as well as unrated bonds determined to be of comparable quality by the Fund’s advisor.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;">The Fund may invest in derivatives such as fixed income futures contracts, fixed income options (including options on swaps), foreign currency exchange forward contracts, currency swaps, interest rate swaps, total return swaps, credit default swaps, or other derivatives.</span> <span style="font-family:Arial;font-size:9.5pt;">As with any investment, an investment in the Fund could lose money over any time period.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">General Market Risk.</span><span style="font-family:Arial;font-size:9.5pt;"> The markets in which the Fund invests can be affected by a variety of factors. These factors, which can be real or perceived, may include economic, market, political, and regulatory conditions and developments as well as local, regional, or global events such as wars, military conflicts, natural disasters, and public health issues. In addition, investor sentiment and expectations regarding these factors can also impact the markets. Different parts of the market, including different industries and sectors as well as different types of securities, may react differently to factors that affect the market. These factors can contribute to market uncertainty, </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">market volatility, and fluctuations in the value of the Fund’s investments, thereby resulting in potential losses to the Fund over short or long periods.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Bond Markets</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund may be impacted by the general condition of the bond markets and by factors that affect bonds and bond issuers. For example, as a general rule, bond prices and interest rates move in opposite directions. When interest rates rise, bond prices tend to fall, and when interest rates fall, bond prices tend to go up. Bond income also is affected by changes in interest rates. Interest rates can rise or fall for a number of reasons, including, but not limited to, central bank monetary policy, inflationary or deflationary pressures, and changes in general market and economic conditions. Changing interest rates, including, but not limited to, rates that fall below zero, could have unpredictable effects on the overall market and may expose the bond markets in particular to heightened volatility and potential illiquidity. The degree to which the Fund is impacted by certain bond market risks may vary based on factors disclosed in its principal investment strategies, such as the types of bonds in which it invests and the overall credit quality, average maturity, and/or average duration of its bond holdings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Interest Rate Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> During periods of rising interest rates, bond prices overall may decline, which could result in a decline in the Fund’s value. The prices of longer-term bonds are more sensitive to changes in interest rates than the prices of shorter-term bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Income Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">During periods of falling interest rates,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">the Fund’s income may decline. The income paid by shorter-term bonds is</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">subject to a higher degree of fluctuation than the income</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">paid by longer-term</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">bonds.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Credit Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Credit risk refers to the chance that an issuer will default (fail to meet its credit obligations) or fail to make payments in a timely manner, which could result in a loss to the Fund.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">negative perceptions of an issuer’s ability to make payments can cause the price of a security to decline. While all debt securities are subject to credit risk to some extent, those with higher credit quality ratings generally pose less credit risk than those with lower credit quality</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">ratings.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Bond Liquidity Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> If the Fund is unable to sell a security at an advantageous time or price, its returns may be reduced.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">There may be limited trading in the secondary</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">market for certain debt securities, which could make them more difficult to value or</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">sell.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds held by the Fund may be callable.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The issuer of a callable bond</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">has the right to “call” (redeem) the bond before its maturity date. Calls on bonds held by the Fund would result in the Fund losing any price appreciation above the bond’s call price.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">In addition, because bond calls occur more frequently during periods of falling interest rates, the Fund likely would be forced to reinvest the proceeds of any called bonds at a lower interest rate than that of the called bonds, resulting in a decline in the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">income and a potential loss in the value of the Fund’s investments. Frequent bond calls and subsequent reinvestments of the proceeds also would increase the Fund’s turnover</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Prepayment Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain bonds are subject to risks associated with prepayment.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Prepayment risk</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">for callable bonds is described under</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Call Risk</span><span style="font-family:Arial;font-size:9.5pt;">. With</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">respect to mortgage-backed,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">asset-backed, and similar debt securities, prepayment typically refers to borrowers repaying their debt early (e.g., before the maturity date). Prepayment of bonds held by the Fund</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">would result in the Fund losing any price appreciation above the amount repaid (or the bond’s call price,</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">in the case of callable bonds). In addition, because prepayments occur more frequently in low interest rate environments, the Fund likely would be forced to reinvest the proceeds from any prepayments at a lower interest rate than when the prepaid bonds were purchased, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments. Frequent prepayments and subsequent reinvestment of the proceeds also would increase the Fund’s turnover rate.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Extension Risk</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">. </span><span style="font-family:Arial;font-size:9.5pt;">During periods of rising interest rates, certain bonds held by the Fund may be paid off substantially more slowly than originally anticipated. As a result, the value of the bonds may fall, resulting in a decline in the Fund’s income and a potential loss in the value of the Fund’s investments.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Active Management.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The Fund is actively managed.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The advisor’s security selection and/or strategy execution could cause the Fund to underperform relevant securities markets or other funds with a similar investment objective.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Management of Certain Similar Funds</span><span style="font-family:Arial;font-size:9.5pt;">. The name, investment objective, principal investment strategies, and risks of the Fund are similar to another separate fund managed by the Fund’s portfolio managers. However, the investment results of the Fund may be higher or lower than, and there is no guarantee that the investment results of the Fund will be comparable to, that other</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">fund.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Investing in Derivatives</span><span style="font-family:Arial;font-size:9.5pt;">. Investing in derivatives may present risks different from, and/or greater than, those associated with investing directly in stocks, bonds, or other types of investments. Derivatives could expose the Fund to increased volatility and/or</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">significant</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">loss.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Certain derivatives have an inherent leverage component, providing the Fund</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">exposure to a sizable position in an underlying asset with a relatively small upfront investment at the time the Fund enters into the derivatives position. For these derivatives, an adverse change in the value or price of the underlying asset could result in a loss substantially greater than the amount invested in the derivative itself. Some derivatives require the Fund to enter into a contract with a counterparty. If the counterparty is unable or unwilling to fulfill its contractual obligation, the Fund may experience a loss. A liquid market may not always exist for the Fund’s derivatives positions. The Fund may be unable to sell or otherwise exit its derivatives position at desired times or prices, which could also result in a loss to the Fund. Some derivatives, particularly OTC derivatives, can be </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">complex and often are valued subjectively. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Fund.</span> <br/><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">Derivatives may not perform as intended, which may result in losses to the Fund. For example, derivatives used for hedging or as a substitute for a portfolio instrument may not provide the expected benefits, particularly during adverse market conditions.</span><span style="font-family:Arial;font-size:9.5pt;"> The use of derivatives is also subject to legal risk, </span><span style="font-family:Arial;font-size:9.5pt;margin-left:0.0pt;">which includes the risk of loss resulting from insufficient or unenforceable contractual documentation, insufficient capacity or authority of the Fund’s counterparty, and operational risk, which includes documentation or settlement issues, system failures, inadequate controls, and human</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">error.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">ETF Share Trading</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;"> The Fund’s ETF shares are listed for trading on Cboe BZX Exchange, Inc. and individual investors may only buy and sell them on the secondary market at market prices. Although it is expected that the market price of an ETF share typically will approximate its net asset value (NAV), there may be times when the market price of an ETF share and its NAV differ significantly. Disruptions to creation and redemption transactions, the existence of significant market volatility, or potential lack of an active trading market for ETF shares (including through a trading halt), as well as other factors, may result in ETF shares trading significantly above (at a premium) or below (at a discount) the Fund’s NAV or the intraday value of the Fund’s holdings. Thus, you may pay more or less than NAV when you buy ETF shares on the secondary market, and you may receive more or less than NAV when you sell those shares.</span> <span style="font-family:Arial;font-size:9.5pt;margin-left:-8.6pt;">• </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;font-weight:bold;">Authorized Participants</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;">.</span><span style="font-family:Arial;font-size:9.5pt;font-weight:bold;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">Only Authorized Participants may engage in creation or redemption transactions directly with the Fund.</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">The Fund has a limited number of financial institutions that may act as Authorized Participants. The Fund’s Authorized Participants are not obligated to engage in creation or redemption transactions. To the extent that the Fund’s Authorized Participants are unable to or choose not to</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">proceed with creation and/or redemption transactions with respect to the Fund and no other Authorized Participants step forward to engage in creation or redemption transactions with the Fund, the Fund’s ETF shares may trade at a discount to NAV and possibly face trading halts and/or</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">delisting.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;font-weight:bold;">An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</span> <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Total Returns</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s ETF shares (based on NAV) </span><span style="font-family:Arial;font-size:9.5pt;">has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Fund compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund. </span><span style="font-family:Arial;font-size:9.5pt;">Keep in mind that the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;">past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span><span style="font-family:Arial;font-size:9.5pt;"> Updated performance information is available on our </span><span style="font-family:Arial;font-size:9.5pt;">website at </span><span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span><span style="font-family:Arial;font-size:9.5pt;">.</span> <span style="font-family:Arial;font-size:9.5pt;">The following bar chart and table show the Fund’s historical performance and are intended to help you understand the risks of investing in the Fund. The bar chart shows how the performance of the Fund’s ETF shares (based on NAV) </span><span style="font-family:Arial;font-size:9.5pt;">has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Fund compare with those of a broad-based securities market index and one or more</span><span style="font-family:Arial;font-size:9.5pt;line-height:11.5pt;"> </span><span style="font-family:Arial;font-size:9.5pt;">additional indexes with similar investment characteristics as the Fund. </span> <span style="font-family:Arial;font-size:9.5pt;">Keep in mind that the Fund’s </span><span style="font-family:Arial;font-size:9.5pt;">past performance (before and after taxes) does not indicate how the Fund will perform in the future.</span> <span style="font-family:Arial;font-size:9.5pt;font-style:italic;">vanguard.com/performance</span> <span style="font-family:Arial;font-size:8pt;font-weight:bold;">Annual Total Returns — Vanguard Ultra-Short Bond ETF Shares</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">During the periods shown in the bar chart, the highest and lowest returns for a calendar quarter were:</span> <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Highest</span> 0.0219 2024-09-30 <span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Lowest</span> -0.0102 2022-03-31 <span style="font-family:Arial;font-size:8.5pt;font-weight:bold;">Average Annual Total Returns for Periods Ended December 31, 2025</span> 2021-04-05 0.0522 0.0337 0.0326 0.0195 0.0307 0.0196 0.0520 0.0338 0.0431 0.0300 0.0730 0.0030 <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Actual after-tax returns depend on your tax situation and may differ from those shown in the preceding table. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">upon redemption. State and local income taxes are not reflected in the calculations. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">When after-tax returns are calculated, it is </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">assumed that the shareholder was in the highest individual federal marginal income tax bracket at the time of each distribution of income or capital gains or </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">upon redemption. State and local income taxes are not reflected in the calculations. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Please note that after-tax returns are not relevant for a </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;">shareholder who holds fund shares in a tax-deferred account, such as an individual retirement account or a 401(k) plan. </span> <span style="color:#000000;font-family:Arial;font-size:9.5pt;">Also, figures captioned </span><span style="color:#000000;font-family:Arial;font-size:9.5pt;font-style:italic;">Return After Taxes on Distributions and Sale of Fund Shares</span><span style="color:#000000;font-family:Arial;font-size:9.5pt;"> may be higher than other figures for the same period if a capital loss occurs upon redemption and results in an assumed tax deduction for the shareholder.</span> None through Vanguard (Broker fees vary) None through Vanguard (Broker fees vary) The expense information shown in the table has been restated to reflect current fees. None through Vanguard (Broker fees vary) The expense information shown in the table has been restated to reflect current fees. None through Vanguard (Broker fees vary) The expense information shown in the table has been restated to reflect current fees. None through Vanguard (Broker fees vary)