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Portfolio Investment Objective The Portfolio seeks to provide current income while maintaining liquidity and a stable share price of $1. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Annual Portfolio Operating Expenses<br /><br />(Expenses that you pay each year as a percentage of the value of your investment) Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Principal Investment Policies The Portfolio invests primarily in high-quality, short-term money market instruments, including certificates of deposit, banker’s acceptances, commercial paper, Eurodollar and Yankee obligations, and other money market securities. To be considered high quality, a security generally must be rated in one of the two highest credit-quality categories for short-term securities by at least two nationally recognized rating services (or by one, if only one rating service has rated the security). If unrated, the security must be determined by Vanguard to be of quality equivalent to securities in the two highest credit-quality categories. The Portfolio invests more than 25% of its assets in securities issued by companies in the financial services industry. The Portfolio maintains a dollar-weighted average maturity of 60 days or less and a dollar-weighted average life of 120 days or less. Principal Risks The Portfolio is designed for investors with a low tolerance for risk; however, the Portfolio is subject to the following risks, which could affect the Portfolio’s performance:<br /><br /> Income risk, which is the chance that the Portfolio’s income will decline because of falling interest rates. Because the Portfolio’s income is based on short-term interest rates—which can fluctuate significantly over short periods—income risk is expected to be high.<br /><br /> Manager risk, which is the chance that poor security selection will cause the Portfolio to underperform relevant benchmarks or other funds with a similar investment objective.<br /><br /> Credit risk, which is the chance that the issuer of a security will fail to pay interest or principal in a timely manner, or that negative perceptions of the issuer’s ability to make such payments will cause the price of that security to decline. Credit risk should be very low for the Portfolio because it invests primarily in securities that are considered to be of high quality.<br /><br /> Foreign investment risk. The Portfolio’s investment in Eurodollar and Yankee obligations, which include certificates of deposit issued in U.S. dollars by foreign banks and foreign branches of U.S. banks, subjects it to the same risks as U.S. money market instruments, such as income risk and credit risk. Additional risks of Eurodollar and Yankee obligations include the chance that a foreign government will not let U.S. dollar-denominated assets leave the country, the chance that the banks that issue Eurodollar obligations may not be subject to the same regulations as U.S. banks, and the chance that adverse political or economic developments will affect investments in a foreign country.<br /><br /> Industry concentration risk, which is the chance that there will be overall problems affecting a particular industry. Because the Portfolio invests more than 25% of its assets in securities issued by companies in the financial services industry, the Portfolio’s performance depends to a greater extent on the overall condition of that industry and is more susceptible to events affecting that industry.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Although the Portfolio seeks to preserve the value of your investment at $1 per share, it is possible to lose money by investing in the Portfolio. Annual Total Returns The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and a comparative benchmark, which have investment characteristics similar to those of the Portfolio. The Portfolio's returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio's returns, the returns would be lower. Returns for the Variable Insurance Money Market Funds Average are derived from data provided by Lipper, a Thomson Reuters Company. Keep in mind that the Portfolio's past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. Average Annual Total Returns for Periods Ended December 31, 2015 16 52 90 205 0.0015 0.0003 0 0.0013 0.0004 -0.0001 0.0144 0.0116 0.0115 During the periods shown in the bar chart, the highest return for a calendar quarter was 1.32% (quarter ended December 31, 2006), and the lowest return for a quarter was 0.02% (quarter ended September 30, 2014). 0.0013 0 0.0003 0.0016 Short-Term Investment-Grade Portfolio Investment Objective The Portfolio seeks to provide current income while maintaining limited price volatility. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) 16 52 90 205 The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and a comparative benchmark, which have investment characteristics similar to those of the Portfolio. 800-522-5555 advisors.vanguard.com highest return 2006-12-31 0.0132 lowest return 2014-09-30 0.0002 The Portfolio invests more than 25% of its assets in securities issued by companies in the financial services industry. Although the Portfolio seeks to preserve the value of your investment at $1 per share, it is possible to lose money by investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. 0.0503 0.0525 0.0283 0.0062 0.0023 0.0017 0.0014 0.0011 0.001 0.0015 Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Portfolio Turnover The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 74% of the average value of its portfolio. Principal Investment Strategies The Portfolio invests in a variety of high-quality and, to a lesser extent, medium-quality fixed income securities. Under normal circumstances, at least 80% of the Portfolio’s assets will be invested in short- and intermediate-term investment-grade securities. The Portfolio’s 80% policy may be changed only upon 60 days’ notice to shareholders. High-quality fixed income securities are those rated the equivalent of A3 or better by Moody’s Investors Service, Inc. (Moody’s), or by another independent rating agency or, if unrated, are determined to be of comparable quality by the Portfolio’s advisor; medium-quality fixed income securities are those rated the equivalent of Baa1, Baa2, or Baa3 by Moody’s or another independent rating agency, or, if unrated, are determined to be of comparable quality by the Portfolio’s advisor. (Investment-grade fixed income securities are those rated the equivalent of Baa3 and above by Moody’s.) The Portfolio is expected to maintain a dollar-weighted average maturity of 1 to 4 years. Principal Risks The Portfolio is designed for investors with a low tolerance for risk; however, you could still lose money by investing in it. The Portfolio is subject to the following risks, which could affect the Portfolio’s performance:<br /><br /> Income risk, which is the chance that the Portfolio’s income will decline because of falling interest rates. Income risk is generally high for short-term bond funds, so investors should expect the Portfolio’s monthly income to fluctuate.<br /><br /> Interest rate risk, which is the chance that bond prices will decline because of rising interest rates. Interest rate risk should be low for the Portfolio because it invests primarily in short-term bonds, whose prices are less sensitive to interest rate changes than are the prices of longer-term bonds.<br /><br /> Credit risk, which is the chance that a bond issuer will fail to pay interest or principal in a timely manner, or that negative perceptions of the issuer’s ability to make such payments will cause the price of that bond to decline. Although the Portfolio invests a limited portion of its assets in low-quality bonds, credit risk should be low for the Portfolio because it invests primarily in bonds that are considered high-quality and, to a lesser extent, in bonds that are considered medium-quality.<br /><br /> Call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. The Portfolio would then lose any price appreciation above the bond’s call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Portfolio’s income. Such redemptions and subsequent reinvestments would also increase the Portfolio’s turnover rate. Call risk should be low for the Portfolio.<br /><br /> Extension risk, which is the chance that during periods of rising interest rates, certain debt securities will be paid off substantially more slowly than originally anticipated, and the value of those securities may fall. Extension risk is generally low for short-term bond funds.<br /><br /> Liquidity risk, which is the chance that the Portfolio may not be able to sell a security in a timely manner at a desired price.<br /><br />Liquidity risk is generally low for short-term corporate bonds.<br /><br /> Manager risk, which is the chance that poor security selection will cause the Portfolio to underperform relevant benchmarks or other funds with a similar investment objective.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. During the periods shown in the bar chart, the highest return for a calendar quarter was 5.92% (quarter ended June 30, 2009), and the lowest return for a quarter was –2.98% (quarter ended September 30, 2008). Average Annual Total Returns for Periods Ended December 31, 2015 <b>Annual Total Returns — Money Market Portfolio</b> Annual Total Returns The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index, which has investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. <b>Annual Total Returns — Short-Term Investment-Grade Portfolio </b> Keep in mind that the Portfolio's past performance does not indicate how the Portfolio will perform in the future. The Portfolio's returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio's returns, the returns would be lower. <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000016 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000017 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000034 column period compact * ~</div> 0.0013 Total Bond Market Index Portfolio 0 0.0003 0.0016 Investment Objective 16 The Portfolio seeks to track the performance of a broad, market-weighted bond index. 52 Fees and Expenses 90 The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. 205 0.0112 0.0106 0.0207 0.0255 0.036 0.0407 0.74 The Portfolio is designed for investors with a low tolerance for risk; however, you could still lose money by investing in it. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index, which has investment characteristics similar to those of the Portfolio. 800-522-5555 advisors.vanguard.com The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. highest return 2009-06-30 0.0592 lowest return 2008-09-30 -0.0298 0.0492 0.0593 -0.0345 0.1386 0.0522 0.0202 0.0442 0.0108 0.0176 0.0112 16 52 90 205 Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000024 column period compact * ~</div> Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Portfolio Turnover The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 149% of the average value of its portfolio. <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000026 column period compact * ~</div> Principal Investment Strategies <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000027 column period compact * ~</div> The Portfolio employs an indexing investment approach designed to track the performance of the Barclays U.S. Aggregate Float Adjusted Index. This Index represents a wide spectrum of public, investment-grade, taxable, fixed income securities 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.<br /><br />The Portfolio invests by sampling the Index, meaning that it holds a broadly diversified collection of securities that, in the aggregate, approximates the full Index in terms of key risk factors and other characteristics. All of the Portfolio’s investments will be selected through the sampling process, and under normal circumstances, at least 80% of the Portfolio’s assets will be invested in bonds held in the Index. The Portfolio maintains a dollar-weighted average maturity consistent with that of the Index, which generally ranges between 5 and 10 years. Principal Risks An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio’s share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio’s performance:<br /><br /> Interest rate risk, which is the chance that bond prices will decline because of rising interest rates. Interest rate risk should be moderate for the Portfolio because it invests primarily in short- and intermediate-term bonds, whose prices are less sensitive to interest rate changes than are the prices of long-term bonds.<br /><br /> Income risk, which is the chance that the Portfolio’s income will decline because of falling interest rates. Income risk is generally high for short-term bond funds and moderate for intermediate-term bond funds, so investors should expect the Portfolio’s monthly income to fluctuate accordingly.<br /><br /> Call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. The Portfolio would then lose any price appreciation above the bond’s call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Portfolio’s income. Such redemptions and subsequent reinvestments would also increase the Portfolio’s turnover rate. Call risk should be moderate for the Portfolio because it invests only a portion of its assets in callable bonds.<br /><br /> Prepayment risk, which is the chance that during periods of falling interest rates, homeowners will refinance their mortgages before their maturity dates, resulting in prepayment of mortgage-backed securities held by the Portfolio. The Portfolio would then lose any price appreciation above the mortgage’s principal and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Portfolio’s income. Such prepayments and subsequent reinvestments would also increase the Portfolio’s turnover rate. Prepayment risk is moderate for the Portfolio because it invests only a portion of its assets in mortgage-backed securities.<br /><br /> Extension risk, which is the chance that during periods of rising interest rates, certain debt securities will be paid off substantially more slowly than originally anticipated, and the value of those securities may fall. For funds that invest in mortgage-backed securities, extension risk is the chance that during periods of rising interest rates, homeowners will prepay their mortgages at slower rates. Extension risk is generally moderate for intermediate-term bond funds.<br /><br /> Credit risk, which is the chance that a bond issuer will fail to pay interest or principal in a timely manner, or that negative perceptions of the issuer’s ability to make such payments will cause the price of that bond to decline. Credit risk should be low for the Portfolio because it purchases only bonds that are of investment-grade quality.<br /><br /> Index sampling risk, which is the chance that the securities selected for the Portfolio, in the aggregate, will not provide investment performance matching that of the Portfolio’s target index. Index sampling risk for the Portfolio should be low.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Annual Total Returns The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of its target index and other comparative indexes, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses, but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. During the periods shown in the bar chart, the highest return for a calendar quarter was 4.40% (quarter ended December 31, 2008), and the lowest return for a quarter was –2.50% (quarter ended June 30, 2013). Average Annual Total Returns for Periods Ended December 31, 2015 0.0012 0 0.0003 0.0015 15 48 85 192 <b>Annual Total Returns — Total Bond Market Index Portfolio</b> An investment in the Portfolio could lose money over short or even long periods. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. High Yield Bond Portfolio The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of its target index and other comparative indexes, which have investment characteristics similar to those of the Portfolio. Investment Objective The Portfolio’s returns are net of its expenses, but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. advisors.vanguard.com 800-522-5555 highest return 2008-12-31 The Portfolio seeks to provide a high level of current income. 0.044 Fees and Expenses lowest return The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. 2013-06-30 Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) -0.025 1.49 Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Portfolio Turnover The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 38% of the average value of its portfolio. Principal Investment Strategies The Portfolio invests primarily in a diversified group of high-yielding, higher-risk corporate bonds—commonly known as “junk bonds”—with medium- and lower-range credit-quality ratings. Under normal circumstances, the Portfolio invests at least 80% of its assets in corporate bonds that are rated below Baa by Moody’s Investors Service, Inc. (Moody’s); have an equivalent rating by any other independent bond-rating agency; or, if unrated, are determined to be of comparable quality by the Portfolio’s advisor. The Portfolio’s 80% policy may be changed only upon 60 days’ notice to shareholders.<br /><br />The Portfolio may not invest more than 20% of its assets in any of the following, taken as a whole: bonds with credit ratings lower than B or the equivalent, convertible securities, preferred stocks, and fixed and floating rate loans of medium- to lower-range credit quality. The loans in which the Portfolio may invest will be rated Baa or below by Moody’s; have an equivalent rating by any other independent bond-rating agency; or, if unrated, are determined to be of comparable quality by the Portfolio’s advisor. The Portfolio’s high-yield bonds and loans have mostly short- and intermediate-term maturities. 15 48 85 192 Principal Risks An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio’s share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio’s performance:<br /><br /> Credit risk, which is the chance that a bond or loan issuer will fail to pay interest or principal in a timely manner, or that negative perceptions of the issuer’s ability to make such payments will cause the price of that bond to decline. Credit risk should be high for the Portfolio because it invests primarily in bonds and loans with medium- and lower-range credit-quality ratings.<br /><br /> Income risk, which is the chance that the Portfolio’s income will decline because of falling interest rates. Income risk is generally high for short-term bond funds and moderate for intermediate-term bond funds, so investors should expect the Portfolio’s monthly income to fluctuate accordingly.<br /><br /> Call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. The Portfolio would then lose any price appreciation above the bond’s call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Portfolio’s income. Such redemptions and subsequent reinvestments would also increase the Portfolio’s turnover rate. Call risk should be moderate for the Portfolio because it invests only a portion of its assets in callable bonds.<br /><br /> Interest rate risk, which is the chance that bond or loan prices will decline because of rising interest rates. Interest rate risk should be moderate for the Portfolio because it invests primarily in short- and intermediate-term bonds, whose prices are less sensitive to interest rate changes than are the prices of long-term bonds.<br /><br /> Liquidity risk, which is the chance that the Portfolio may not be able to sell a security in a timely manner at a desired price.<br /><br />Liquidity risk should be low to moderate for the Portfolio.<br /><br /> Manager risk, which is the chance that poor security selection will cause the Portfolio to underperform relevant benchmarks or other funds with a similar investment objective.<br /><br />Because of the speculative nature of junk bonds, you should carefully consider the risks associated with this portfolio.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. 0.0033 0.0055 0.0044 0.0044 0.0306 0.0325 0.0325 0.0325 Annual Total Returns 0.0441 0.0451 0.0452 The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and a composite index, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. During the periods shown in the bar chart, the highest return for a calendar quarter was 14.41% (quarter ended June 30, 2009), and the lowest return for a quarter was –14.60% (quarter ended December 31, 2008). Average Annual Total Returns for Periods Ended December 31, 2015 0.0025 0 0.0003 0.0028 29 90 157 356 0.044 0.0689 0.0523 0.0594 0.065 0.0765 0.0402 -0.0229 0.0589 0.0033 <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000036 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000037 column period compact * ~</div> -0.0158 -0.0447 -0.0253 Balanced Portfolio Investment Objective The Portfolio seeks to provide long-term capital appreciation and reasonable current income. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Portfolio Turnover <b>Annual Total Returns — High Yield Bond Portfolio </b> The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 45% of the average value of its portfolio. Principal Investment Strategies The Portfolio invests 60% to 70% of its assets in dividend-paying and, to a lesser extent, non-dividend-paying common stocks of established large companies. In choosing these companies, the advisor seeks those that appear to be undervalued but have prospects for improvement. These stocks are commonly referred to as value stocks. The remaining 30% to 40% of Portfolio assets are invested mainly in fixed income securities that the advisor believes will generate a reasonable level of current income. These securities include investment-grade corporate bonds, with some exposure to U.S. Treasury and government agency bonds, and mortgage-backed securities. 0.38 Principal Risks The Portfolio is subject to the risks associated with the stock and bond markets, any of which could cause an investor to lose money. However, because stock and bond prices can move in different directions or to different degrees, the Portfolio’s bond holdings may counteract some of the volatility experienced by the Portfolio’s stock holdings.<br /><br /> With approximately 60% to 70% of its assets allocated to stocks, the Portfolio is proportionately subject to the following stock risks: stock market risk, which is the chance that stock prices overall will decline; and investment style risk, which is the chance that returns from large-capitalization value stocks will trail returns from the overall stock market. Large-cap stocks tend to go through cycles of doing better—or worse—than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years.<br /><br /> With approximately 30% to 40% of its assets allocated to bonds, the Portfolio is proportionately subject to the following bond risks: interest rate risk, which is the chance that bond prices will decline because of rising interest rates; income risk, which is the chance that the Portfolio’s income will decline because of falling interest rates; credit risk, which is the chance that a bond issuer will fail to pay interest or principal in a timely manner or that negative perceptions of the issuer’s ability to make such payments will cause the price of that bond to decline; liquidity risk, which is the chance that Portfolio may not be able to sell a security in a timely manner at a desired price; and call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. The Portfolio would then lose any price appreciation above the bond’s call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the Portfolio’s income. Such redemptions and subsequent reinvestments would also increase the Portfolio’s turnover rate. For mortgage-backed securities, this risk is known as prepayment risk.<br /><br /> The Portfolio is also subject to manager risk, which is the chance that poor security selection will cause the Portfolio to underperform relevant benchmarks or other funds with a similar investment objective. In addition, significant investment in the financial sector subjects the Portfolio to proportionately higher exposure to the risks of this sector.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. An investment in the Portfolio could lose money over short or even long periods. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and a composite index, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. advisors.vanguard.com 800-522-5555 highest return 2009-06-30 0.1441 lowest return Annual Total Returns 2008-12-31 -0.146 The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and a composite stock/bond index, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. During the periods shown in the bar chart, the highest return for a calendar quarter was 13.60% (quarter ended June 30, 2009), and the lowest return for a quarter was –10.86% (quarter ended December 31, 2008). Average Annual Total Returns for Periods Ended December 31, 2015 <b>Annual Total Returns — Balanced Portfolio</b> 0.0021 0 0.0002 0.0023 29 90 157 24 356 74 130 293 0.0827 0.0195 -0.2195 0.3885 0.121 0.0693 0.143 0.0435 0.044 -0.0158 24 74 130 293 0.0556 0.0504 0.0523 0.058 0.0696 0.0641 0.1496 0.0836 -0.2257 0.229 0.1102 0.037 0.1256 0.1988 0.0984 0.0009 0.0009 0.0138 0.0138 0.09 0.1257 0.0976 0.0731 0.0731 0.0671 <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000044 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000046 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000047 column period compact * ~</div> 0.45 An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and a composite stock/bond index, which have investment characteristics similar to those of the Portfolio. 800-522-5555 advisors.vanguard.com Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. highest return 2009-06-30 0.136 lowest return 2008-12-31 -0.1086 The Portfolio is subject to the risks associated with the stock and bond markets, any of which could cause an investor to lose money. <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000074 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000076 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000077 column period compact * ~</div> Conservative Allocation Portfolio Moderate Allocation Portfolio Investment Objective Investment Objective The Portfolio seeks to provide current income and low to moderate capital appreciation. The Portfolio seeks to provide capital appreciation and a low to moderate level of current income. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) Example Example The following example is intended to help you compare the cost of investing in the Portfolio (based on the fees and expenses of the underlying funds) with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual operating expenses of the Portfolio and its underlying funds remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: The following example is intended to help you compare the cost of investing in the Portfolio (based on the fees and expenses of the underlying funds) with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual operating expenses of the Portfolio and its underlying funds remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Portfolio Turnover Portfolio Turnover The Portfolio may pay transaction costs, such as purchase fees, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 12% of the average value of its portfolio. The Portfolio may pay transaction costs, such as purchase fees, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 15% of the average value of its portfolio. Principal Investment Strategies Principal Investment Strategies The Portfolio invests in a mix of Vanguard mutual funds and other portfolios of Vanguard Variable Insurance Fund (collectively, the underlying funds) according to an asset-allocation strategy that reflects an allocation of approximately 60% of the Portfolio’s assets to fixed-income securities and 40% to common stocks. The targeted percentage of the Portfolio’s assets allocated to the underlying asset classes is:<br/><br/><table border="0" cellspacing="0"><tr valign="bottom"><td align="left" style="text-indent: 0pt;"></td><td align="left" style="text-indent: 0pt;">U.S. fixed-income securities</td><td align="right">                         48%</td></tr><tr valign="bottom"><td align="left" style="text-indent: 0pt;"></td><td align="left" style="text-indent: 0pt;">Large-cap U.S. stocks</td><td align="right" style="text-indent: 1.019pt;">22%</td></tr><tr valign="bottom"><td align="left" style="text-indent: 0pt;"></td><td align="left" style="text-indent: 0pt;">Foreign stocks</td><td align="right">12%</td></tr><tr valign="bottom"><td align="left"></td><td align="left" style="text-indent: 0pt;">Foreign fixed-income securities</td><td align="right">12%</td></tr><tr valign="bottom"><td align="left"></td><td align="left">Small- and mid-cap U.S. stocks</td><td align="right">6%</td></tr></table><br/>The Portfolio’s indirect fixed-income holdings are a diversified mix of short-, intermediate-, and long-term U.S. government, U.S. agency, and investment-grade U.S corporate bonds; mortgage-backed and asset-backed securities; and government, agency, corporate, and investment-grade foreign bonds issued in currencies other than the U.S. dollar (but hedged by Vanguard, typically with foreign currency exchange forward contracts, to minimize foreign currency exposure). The Portfolio’s indirect stock holdings are a diversified mix of U.S. and foreign large-, mid-, and small-capitalization stocks.<br /><br />The Portfolio uses its investment in large-cap U.S. stocks and small- and mid-cap U.S. stocks to gain exposure to the overall domestic stock market. While the percentage of the Portfolio’s assets invested in either of these two asset classes may deviate slightly from the target allocation, the combination of the two asset classes will equal approximately 28% of the Portfolio’s assets in the aggregate.<br /><br />The Portfolio’s board of trustees may change the targeted allocation to the underlying asset classes without shareholder approval. The Portfolio invests in a mix of Vanguard mutual funds and other portfolios of Vanguard Variable Insurance Fund (collectively, the underlying funds) according to an asset-allocation strategy that reflects an allocation of approximately 60% of the Portfolio’s assets to common stocks and 40% to fixed-income securities. The targeted percentage of the Portfolio’s assets allocated to the underlying asset classes is:<br/><br/><table border="0" cellspacing="0"><tr valign="bottom"><td align="left" style="text-indent: 0pt;"></td><td align="left" style="text-indent: 0pt;">Large-cap U.S. stocks</td><td align="right">                         34%</td></tr><tr valign="bottom"><td align="left" style="text-indent: 0pt;"></td><td align="left" style="text-indent: 0pt;">U.S. fixed-income securities</td><td align="right" style="text-indent: 1.019pt;">32%</td></tr><tr valign="bottom"><td align="left" style="text-indent: 0pt;"></td><td align="left" style="text-indent: 0pt;">Foreign stocks</td><td align="right">18%</td></tr><tr valign="bottom"><td align="left"></td><td align="left" style="text-indent: 0pt;">Foreign fixed-income securities</td><td align="right">8%</td></tr><tr valign="bottom"><td align="left"></td><td align="left">Small- and mid-cap U.S. stocks</td><td align="right">8%</td></tr></table><br/>The Portfolio’s indirect stock holdings are a diversified mix of U.S. and foreign large-, mid-, and small-capitalization stocks. The Portfolio’s indirect fixed-income holdings are a diversified mix of short-, intermediate-, and long-term U.S. government, U.S. agency, and investment-grade U.S. corporate bonds; mortgage-backed and asset-backed securities; and government, agency, corporate, and investment-grade foreign bonds issued in currencies other than the U.S. dollar (but hedged by Vanguard, typically with foreign currency exchange forward contracts, to minimize foreign currency exposure).<br /><br />The Portfolio uses its investment in large-cap U.S. stocks and small- and mid-cap U.S. stocks to gain exposure to the overall domestic stock market. While the percentage of the Portfolio’s assets invested in either of these two asset classes may deviate slightly from the target allocation, the combination of the two asset classes will equal approximately 42% of the Portfolio’s assets in the aggregate.<br /><br />The Portfolio’s boad of trustees may change the targeted allocation to the underlying asset classes without shareholder approval. Principal Risks The Portfolio is subject to the risks associated with the stock and bond markets, any of which could cause an investor to lose money. However, because fixed-income securities such as bonds usually are less volatile than stocks and because the Portfolio invests more than half of its assets in fixed-income securities, the Portfolio’s overall level of risk should be low to moderate.<br /><br /> With a target allocation of approximately 60% of its assets to fixed-income securities, the Portfolio is proportionately subject to bond risks, including the following: interest rate risk, which is the chance that bond prices will decline because of rising interest rates; credit risk, which is the chance that the issuer of a security will fail to pay interest or principal in a timely manner, or that negative perceptions of the issuer’s ability to make such payments will cause the price of that security to decline, thus reducing the underlying fund’s return; and income risk, which is the chance that an underlying fund’s income will decline because of falling interest rates. If an underlying fund holds securities that are callable, the underlying fund’s income may decline because of call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. An underlying fund would then lose any price appreciation above the bond’s call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the underlying fund’s income. Such redemptions and subsequent reinvestments would also increase the Portfolio’s turnover rate. For mortgage-backed securities, this risk is known as prepayment risk. The Portfolio is also subject to the following risks associated with investments in currency-hedged foreign bonds: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value and/or liquidity of securities issued by foreign governments, government agencies, or companies; and currency hedging risk, which is the chance that the currency hedging transactions entered into by the underlying foreign fixed-income securities fund may not perfectly offset the fund’s foreign currency exposure.<br /><br /> With approximately 40% of its assets allocated to stocks, the Portfolio is proportionately subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Portfolio is also subject to the following risks associated with investments in foreign stocks: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value of securities issued by companies in foreign countries or regions; and currency risk, which is the chance that the value of a foreign investment, measured in U.S. dollars, will decrease because of unfavorable changes in currency exchange rates. Country/regional risk and currency risk are especially high in emerging markets.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Principal Risks Annual Total Returns The Portfolio is subject to the risks associated with the stock and bond markets, any of which could cause an investor to lose money. However, because fixed-income securities such as bonds usually are less volatile than stocks and because the Portfolio invests a significant portion of its assets in fixed-income securities, the Portfolio’s overall level of risk should be moderate.<br /><br /> With approximately 60% of its assets allocated to stocks, the Portfolio is proportionately subject to stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Portfolio is also subject to the following risks associated with investments in foreign stocks: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value of securities issued by companies in foreign countries and regions; and currency risk, which is the chance that the value of a foreign investment, measured in U.S. dollars, will decrease because of unfavorable changes in currency exchange rates. Country/regional risk and currency risk are especially high in emerging markets.<br /><br /> With a target allocation of approximately 40% of its assets to fixed-income securities, the Portfolio is proportionately subject to bond risks, including the following: interest rate risk, which is the chance that bond prices will decline because of rising interest rates; credit risk, which is the chance that the issuer of a security will fail to pay interest or principal in a timely manner, or that negative perceptions of the issuer’s ability to make such payments will cause the price of that security to decline, thus reducing the underlying fund’s return; and income risk, which is the chance that an underlying fund’s income will decline because of falling interest rates. If an underlying fund holds securities that are callable, the underlying fund’s income may decline because of call risk, which is the chance that during periods of falling interest rates, issuers of callable bonds may call (redeem) securities with higher coupon rates or interest rates before their maturity dates. An underlying fund would then lose any price appreciation above the bond’s call price and would be forced to reinvest the unanticipated proceeds at lower interest rates, resulting in a decline in the underlying fund’s income. Such redemptions and subsequent reinvestments would also increase the Portfolio’s turnover rate. For mortgage-backed securities, this risk is known as prepayment risk. The Portfolio is also subject to the following risks associated with investments in currency-hedged foreign bonds: country/regional risk, which is the chance that world events—such as political upheaval, financial troubles, or natural disasters—will adversely affect the value and/or liquidity of securities issued by foreign governments, government agencies, or companies; and currency hedging risk, which is the chance that the currency hedging transactions entered into by the underlying foreign fixed-income securities fund may not perfectly offset the fund’s foreign currency exposure.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and other comparative benchmarks, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses, but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Returns for the Variable Insurance Mixed-Asset Target Allocation Conservative Funds Average are derived from data provided by Lipper, a Thomson Reuters Company. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. During the periods shown in the bar chart, the highest return for a calendar quarter was 5.03% (quarter ended March 31, 2012), and the lowest return for a quarter was –2.63% (quarter ended September 30, 2015). Average Annual Total Returns for Periods Ended December 31, 2015 Annual Total Returns The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and other comparative benchmarks, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses, but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Returns for the Variable Insurance Mixed-Asset Target Allocation Moderate Funds Average are derived from data provided by Lipper, a Thomson Reuters Company. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. During the periods shown in the bar chart, the highest return for a calendar quarter was 7.52% (quarter ended March 31, 2012), and the lowest return for a quarter was –4.64% (quarter ended September 30, 2015). Average Annual Total Returns for Periods Ended December 31, 2015 0 0 0 0 0 0 0.0016 0.0016 0.0016 0.0016 16 16 52 52 90 90 205 205 Equity Income Portfolio Investment Objective The Portfolio seeks to provide an above-average level of current income and reasonable long-term capital appreciation. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Portfolio Turnover The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 36% of the average value of its portfolio. Principal Investment Strategies The Portfolio invests mainly in common stocks of mid-size and large companies whose stocks pay above-average levels of dividend income and are considered to have the potential for capital appreciation. In addition, the advisors generally look for companies that they believe are committed to paying dividends consistently. Under normal circumstances, the Portfolio will invest at least 80% of its assets in equity securities. The Portfolio’s 80% policy may be changed only upon 60 days’ notice to shareholders. The Portfolio uses multiple investment advisors. Principal Risks An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio’s share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio’s performance:<br /><br /> Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices.<br /><br /> Investment style risk, which is the chance that returns from mid- and large-capitalization dividend-paying value stocks will trail returns from the overall stock market. Mid- and large-cap stocks each tend to go through cycles of doing better—or worse—than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years. Historically, mid-cap stocks have been more volatile in price than large-cap stocks because, among other things, mid-size companies are more sensitive to changing economic conditions.<br /><br /> Manager risk, which is the chance that poor security selection will cause the Portfolio to underperform relevant benchmarks or other funds with a similar investment objective.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Annual Total Returns The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and other comparative benchmarks, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Returns for the Variable Insurance Equity Income Funds Average are derived from data provided by Lipper, a Thomson Reuters Company. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. During the periods shown in the bar chart, the highest return for a calendar quarter was 15.14% (quarter ended September 30, 2009), and the lowest return for a quarter was –17.99% (quarter ended December 31, 2008). Average Annual Total Returns for Periods Ended December 31, 2015 <b>Annual Total Returns — Equity Income Portfolio</b> 0.0029 0 0.0002 0.0031 32 100 174 393 32 100 174 393 0.207 0.0453 -0.3091 0.1677 0.1471 0.1027 0.134 0.3004 0.1141 0.0085 0.0085 0.0039 0.0039 -0.0402 0.1281 0.1314 0.1314 0.0927 0.0787 0.0758 0.0766 0.0548 Diversified Value Portfolio Investment Objective The Portfolio seeks to provide long-term capital appreciation and income. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Portfolio Turnover The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 13% of the average value of its portfolio. Principal Investment Strategies The Portfolio invests mainly in large- and mid-capitalization companies whose stocks are considered by the advisor to be undervalued. Undervalued stocks are generally those that are out of favor with investors and that the advisor feels are trading at prices that are below average in relation to such measures as earnings and book value. These stocks often have above-average dividend yields. Principal Risks An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio’s share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio’s performance:<br /><br /> Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices.<br /><br /> Investment style risk, which is the chance that returns from large- and mid-capitalization value stocks will trail returns from the overall stock market. Large- and mid-cap stocks each tend to go through cycles of doing better—or worse—than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years. Historically, mid-cap stocks have been more volatile in price than large-cap stocks because, among other things, mid-size companies are more sensative to changing economic conditions.<br /><br /> Asset concentration risk, which is the chance that the Portfolio’s performance may be hurt disproportionately by the poor performance of relatively few stocks. The Portfolio tends to invest a high percentage of assets in its ten largest holdings.<br /><br /> Manager risk, which is the chance that poor security selection will cause the Portfolio to underperform relevant benchmarks or other funds with a similar investment objective. In addition, significant investment in the financial sector subjects the Portfolio to proportionately higher exposure to the risks of this sector.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Annual Total Returns The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index, which has investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. During the periods shown in the bar chart, the highest return for a calendar quarter was 18.07% (quarter ended June 30, 2009), and the lowest return for a quarter was –20.32% (quarter ended December 31, 2008). Average Annual Total Returns for Periods Ended December 31, 2015 0.0025 0 0.0003 0.0028 0.36 An investment in the Portfolio could lose money over short or even long periods. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. 29 90 157 356 The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and other comparative benchmarks, which have investment characteristics similar to those of the Portfolio. 800-522-5555 advisors.vanguard.com Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. 0.1888 0.0393 -0.3614 0.2692 0.0933 The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. 0.15 The Portfolio is subject to the risks associated with the stock and bond markets, any of which could cause an investor to lose money. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and other comparative benchmarks, which have investment characteristics similar to those of the Portfolio. 29 The Portfolio’s returns are net of its expenses, but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. 90 Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. 157 advisors.vanguard.com 356 800-522-5555 highest return 2012-03-31 0.0503 lowest return 2015-09-30 -0.0263 0.002 0.0044 0.0032 -0.0128 0.0653 0.0239 0.067 0.0505 2011-10-19 2011-10-19 2011-10-19 2011-10-19 -0.0245 -0.0383 0.1091 highest return 0.1127 2009-09-30 0.0627 0.0616 0.1514 lowest return 2008-12-31 -0.1799 0.0925 0.0691 0.0906 0.002 16 52 90 205 <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000084 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000054 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000056 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000086 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000057 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000087 column period compact * ~</div> <b>Annual Total Returns — Moderate Allocation Portfolio</b> <b>Annual Total Returns — Conservative Allocation Portfolio</b> <b>Annual Total Returns — Diversified value portfolio</b> -0.0016 0.0044 0.0003 -0.0143 0.0846 0.1556 0.0866 0.0738 2011-10-19 2011-10-19 2011-10-19 2011-10-19 An investment in the Portfolio could lose money over short or even long periods. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index, which has investment characteristics similar to those of the Portfolio. 800-522-5555 advisors.vanguard.com 0.12 The Portfolio is subject to the risks associated with the stock and bond markets, any of which could cause an investor to lose money. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and other comparative benchmarks, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses, but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. advisors.vanguard.com 800-522-5555 highest return 2012-03-31 0.0752 lowest return 2015-09-30 -0.0464 The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. 0.1184 0.1502 0.0703 -0.0016 highest return 2009-06-30 0.1807 lowest return 2008-12-31 -0.2032 <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000094 column period compact * ~</div> 16 52 90 205 Equity Index Portfolio Investment Objective <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000064 column period compact * ~</div> The Portfolio seeks to track the performance of a benchmark index that measures the investment return of large-capitalization stocks. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000066 column period compact * ~</div> Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000067 column period compact * ~</div> Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Portfolio Turnover The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 4% of the average value of its portfolio. Principal Investment Strategies The Portfolio employs an indexing investment approach designed to track the performance of the Standard & Poor’s 500 Index, a widely recognized benchmark of U.S. stock market performance that is dominated by the stocks of large U.S. companies. The Portfolio attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index. Principal Risks An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio’s share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio’s performance:<br /><br /> Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Portfolio’s target index tracks a subset of the U.S. stock market, which could cause the Portfolio to perform differently from the overall stock market. In addition, the Portfolio’s target index may, at times, become focused in stocks of a particular market sector, which would subject the Portfolio to proportionately higher exposure to the risks of that sector.<br /><br /> Investment style risk, which is the chance that returns from large-capitalization stocks will trail returns from the overall stock market. Large-cap stocks tend to go through cycles of doing better—or worse—than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Annual Total Returns The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of its target index, which has investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses, but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. During the periods shown in the bar chart, the highest return for a calendar quarter was 15.95% (quarter ended June 30, 2009), and the lowest return for a quarter was –21.84% (quarter ended December 31, 2008). Average Annual Total Returns for Periods Ended December 31, 2015 <b>Annual Total Returns — Equity Index Portfolio</b> 0.0012 0 0.0003 0.0015 15 48 85 192 0.0392 0.165 0.294 0.0983 -0.0245 15 48 <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000097 column period compact * ~</div> 85 <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000096 column period compact * ~</div> 192 0.1571 0.0538 -0.3693 0.2644 0.1491 0.0193 0.1586 0.13 0.3218 0.1351 0.0127 0.0127 0.0138 0.124 0.1257 0.072 0.0731 0.04 An investment in the Portfolio could lose money over short or even long periods. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of its target index, which has investment characteristics similar to those of the Portfolio. 800-522-5555 advisors.vanguard.com Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Total Stock Market Index Portfolio Investment Objective The Portfolio seeks to track the performance of a benchmark index that measures the investment return of the overall stock market. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) Example The following example is intended to help you compare the cost of investing in the Portfolio (based on the fees and expenses of the underlying funds) with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual operating expenses of the Portfolio and its underlying funds remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: The Portfolio’s returns are net of its expenses, but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Portfolio Turnover The Portfolio may pay transaction costs, such as purchase fees, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 5% of the average value of its portfolio. Principal Investment Strategies The Portfolio employs an indexing investment approach designed to track the performance of the Standard & Poor’s (S&P) Total Market Index by investing all, or substantially all, of its assets in two Vanguard funds—Vanguard Variable Insurance Fund Equity Index Portfolio and Vanguard Extended Market Index Fund. The S&P Total Market Index consists of substantially all of the U.S. common stocks regularly traded on the New York Stock Exchange and the Nasdaq over-the-counter market. Principal Risks highest return An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio’s share price and total return to fluctuate within a wide range. Though the Portfolio seeks to track the Index, its performance typically can be expected to fall short by a small percentage representing operating costs of the underlying funds. The Portfolio is subject to the following risk, which could affect the Portfolio’s performance:<br /><br /> Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. In addition, the Portfolio’s target index may, at times, become focused in stocks of a particular market sector, which would subject the Portfolio to proportionately higher exposure to the risks of that sector.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. 2009-06-30 0.1595 Annual Total Returns lowest return The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of its target index and other comparative indexes, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. 2008-12-31 -0.2184 During the periods shown in the bar chart, the highest return for a calendar quarter was 16.95% (quarter ended June 30, 2009), and the lowest return for a quarter was –22.75% (quarter ended December 31, 2008). Average Annual Total Returns for Periods Ended December 31, 2015 0 0 0 0.0016 0.0016 <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000114 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000116 column period compact * ~</div> Growth Portfolio Investment Objective The Portfolio seeks to provide long-term capital appreciation. <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000117 column period compact * ~</div> Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) Capital Growth Portfolio Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Investment Objective Portfolio Turnover The Portfolio seeks to provide long-term capital appreciation. The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 38% of the average value of its portfolio. Principal Investment Strategies The Portfolio invests mainly in large-capitalization stocks of U.S. companies considered to have above-average earnings growth potential and reasonable stock prices in comparison with expected earnings. The Portfolio uses multiple investment advisors. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Principal Risks Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio's share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio's performance:<br /><br /> Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices.<br /><br /> Investment style risk, which is the chance that returns from large-capitalization growth stocks will trail returns from the overall stock market. Large-cap growth stocks tend to go through cycles of doing better—or worse—than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years.<br /><br /> Asset concentration risk, which is the chance that the Portfolio's performance may be hurt disproportionately by the poor performance of relatively few stocks. The Portfolio tends to invest a high percentage of assets in its ten largest holdings.<br /><br /> Manager risk, which is the chance that poor security selection will cause the Portfolio to underperform relevant benchmarks or other funds with a similar investment objective. In addition, significant investment in the information technology sector subjects the Portfolio to proportionately higher exposure to the risks of this sector.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Example Annual Total Returns The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of relevant market indexes, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: During the periods shown in the bar chart, the highest return for a calendar quarter was 18.12% (quarter ended March 31, 2012), and the lowest return for a quarter was –21.54% (quarter ended December 31, 2008). Portfolio Turnover Average Annual Total Returns for Periods Ended December 31, 2015 The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 5% of the average value of its portfolio. 16 52 Principal Investment Strategies 90 The Portfolio invests in stocks considered to have above-average earnings growth potential that is not reflected in their current market prices. The Portfolio consists predominantly of large- and mid-capitalization stocks. 205 Principal Risks An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio’s share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio’s performance:<br /><br /> Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices.<br /><br /> Investment style risk, which is the chance that returns from mid- and large-capitalization growth stocks will trail returns from the overall stock market. Mid- and large-cap stocks each tend to go through cycles of doing better—or worse—than other segments of the stock market or the stock market in general. These periods have, in the past, lasted for as long as several years. Historically, mid-cap stocks have been more volatile in price than large-cap stocks.<br /><br /> Asset concentration risk, which is the chance that the Portfolio’s performance may be hurt disproportionately by the poor performance of relatively few stocks. The Portfolio tends to invest a high percentage of assets in its ten largest holdings.<br /><br /> Manager risk, which is the chance that poor security selection will cause the Portfolio to underperform relevant benchmarks or other funds with a similar investment objective. In addition, significant investments in the health care and information technology sectors subject the Portfolio to proportionately higher exposure to the risks of these sectors.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Annual Total Returns The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index, which has investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses, but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. During the periods shown in the bar chart, the highest return for a calendar quarter was 14.43% (quarter ended September 30, 2009), and the lowest return for a quarter was –21.64% (quarter ended December 31, 2008). Under normal circumstances the Portfolio invests at least 80% of its assets primarily in common stocks of small companies. These companies tend to be unseasoned but are considered by the Portfolio's advisors to have superior growth potential. Also, these companies often provide little or no dividend income. The Portfolio's 80% policy may be changed only upon 60 days' notice to shareholders. The Portfolio uses multiple investment advisors. An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio's share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio's performance:<br /><br /> Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices.<br /><br /> Investment style risk, which is the chance that returns from small-capitalization growth stocks will trail returns from the overall stock market. Historically, small-cap stocks have been more volatile in price than the large-cap stocks that dominate the overall market, and they often perform quite differently. Small companies tend to have greater stock volatility because, among other things, these companies are more sensitive to changing economic conditions.<br /><br /> Manager risk, which is the chance that poor security selection will cause the Portfolio to underperform relevant benchmarks or other funds with a similar investment objective. In addition, significant investment in the information technology sector subjects the Portfolio to proportionately higher exposure to the risks of this sector.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000154 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000157 column period compact * ~</div> Average Annual Total Returns for Periods Ended December 31, 2015 16 52 90 205 0.0041 0.0033 0 0 0.0003 0.0003 0.0044 0.0036 0.1552 0.0516 -0.3728 0.2826 0.1711 Small Company Growth Portfolio Investment Objective 0.0083 0.1633 0.3328 The Portfolio seeks to provide long-term capital appreciation. 0.1229 0.0037 Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. “Acquired Fund Fees and Expenses” are expenses incurred indirectly by the Portfolio through its ownership of shares in other investment companies, such as business development companies. Business development company expenses are similar to the expenses paid by any operating company held by the Portfolio. They are not direct costs paid by Portfolio shareholders and are not used to calculate the Portfolio’s net asset value. They have no impact on the costs associated with portfolio operations. Annual Portfolio Operating Expenses<br /><br />(Expenses that you pay each year as a percentage of the value of your investment) 45 0.0037 0.0044 0.0047 0.0047 The Portfolio invests predominantly in the stocks of companies located outside the United States and is expected to diversify its assets in countries across developed and emerging markets. In selecting stocks, the Portfolio's advisors evaluate foreign markets around the world and choose large-, mid-, and small-capitalization companies considered to have above-average growth potential. The Portfolio uses multiple investment advisors. An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio's share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio's performance:<br /><br /> Investment style risk, which is the chance that returns from non-U.S. growth stocks, and, to the extent that the Portfolio is invested in them, small- and mid-capitalization stocks, will trail returns from global stock markets. Historically, non-U.S. small-and mid-cap stocks have been more volatile in price than the large-cap stocks that dominate the global markets, and they often perform quite differently.<br /><br /> Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. In addition, investments in foreign stocks can be riskier than U.S. stock investments. Foreign stocks tend to be more volatile and less liquid than U.S. stocks. The prices of foreign stocks and the prices of U.S. stocks may move in opposite directions.<br /><br /> Country/regional risk, which is the chance that world eventssuch as political upheaval, financial troubles, or natural disasterswill adversely affect the value of securities issued by companies in foreign countries or regions. Because the Portfolio may invest a large portion of its assets in securities of companies located in any one country or region, including emerging markets, the Portfolio's performance may be hurt disproportionately by the poor performance of its investments in that area. Country/regional risk is especially high in emerging markets.<br /><br /> Currency risk, which is the chance that the value of a foreign investment, measured in U.S. dollars, will decrease because of unfavorable changes in currency exchange rates. Currency risk is especially high in emerging markets.<br /><br /> Manager risk, which is the chance that poor security selection will cause the Portfolio to underperform relevant benchmarks or other funds with a similar investment objective. In addition, significant investment in the financial sector subjects the Portfolio to proportionately higher exposure to the risks of this sector.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000164 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000167 column period compact * ~</div> 0.0034 0.12 0.1214 0.1211 0.1211 37 0 141 116 0.0727 0.0748 0.0735 0.0735 202 246 456 0.0003 555 0.0001 0.0038 Example International Portfolio The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Investment Objective Portfolio Turnover The Portfolio seeks to provide long-term capital appreciation. The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 57% of the average value of its portfolio. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Principal Investment Strategies Annual Portfolio Operating Expenses<br /><br />(Expenses that you pay each year as a percentage of the value of your investment) Principal Risks Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Annual Total Returns Portfolio Turnover The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index, which has investment characteristics similar to those of the Portfolio. The Portfolio's returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio's returns, the returns would be lower. Keep in mind that the Portfolio's past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 23% of the average value of its portfolio. During the periods shown in the bar chart, the highest return for a calendar quarter was 20.18% (quarter ended June 30, 2009), and the lowest return for a quarter was –25.40% (quarter ended December 31, 2008). Principal Investment Strategies Average Annual Total Returns for Periods Ended December 31, 2015 Principal Risks 39 122 Annual Total Returns 213 The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and a comparative index, which have investment characteristics similar to those of the Portfolio. Returns for the Indexes shown are adjusted for withholding taxes. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. 480 During the periods shown in the bar chart, the highest return for a calendar quarter was 27.23% (quarter ended June 30, 2009), and the lowest return for a quarter was –23.31% (quarter ended December 31, 2008). Average Annual Total Returns for Periods Ended December 31, 2015 -0.0275 -0.0019 0.1135 0.1143 0.0037 0.0809 0.0849 0 0.0003 0.004 0.0798 0.0567 0.0138 0.1431 0.1353 0.1257 0.0751 0.0853 0.0731 0.1021 0.0262 0.0138 0.0377 41 -0.3947 0.14 0.1257 <b>Annual Total Returns — Total Stock Market Index Portfolio</b> 128 0.4107 224 0.3179 505 0.0136 0.1465 Mid-Cap Index Portfolio 0.4654 0.0338 -0.0275 Investment Objective The Portfolio seeks to track the performance of a benchmark index that measures the investment return of mid-capitalization stocks. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) 0.0984 0.0731 Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Portfolio Turnover The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 23% of the average value of its portfolio. Principal Investment Strategies The Portfolio employs an indexing investment approach designed to track the performance of the CRSP US Mid Cap Index, a broadly diversified index of stocks of mid-size U.S. companies. The Portfolio attempts to replicate the target index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index. Principal Risks An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio’s share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio’s performance:<br /><br /> Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Portfolio’s target index tracks a subset of the U.S. stock market, which could cause the Portfolio to perform differently from the overall stock market. In addition, the Portfolio’s target index may, at times, become focused in stocks of a particular market sector, which would subject the Portfolio to proportionately higher exposure to the risks of that sector.<br /><br /> Investment style risk, which is the chance that returns from mid-capitalization stocks will trail returns from the overall stock market. Historically, mid-cap stocks have been more volatile in price than the large-cap stocks that dominate the overall market, and they often perform quite differently.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. <b>Annual Total Returns — Small Company Growth Portfolio</b> 0.0191 0.1022 -0.3772 0.3505 0.1181 -0.0084 0.1843 0.3528 Annual Total Returns 0.1379 0.0798 The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of the Portfolio’s target index and other comparative indexes, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. During the periods shown in the bar chart, the highest return for a calendar quarter was 21.44% (quarter ended September 30, 2009), and the lowest return for a quarter was –25.65% (quarter ended December 31, 2008). Average Annual Total Returns for Periods Ended December 31, 2015 0.05 The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index, which has investment characteristics similar to those of the Portfolio. The Portfolio's returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio's returns, the returns would be lower. Keep in mind that the Portfolio's past performance does not indicate how the Portfolio will perform in the future. advisors.vanguard.com 800-522-5555 An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. An investment in the Portfolio could lose money over short or even long periods. 0.57 Acquired Fund Fees and Expenses are not included in the Portfolio's financial statements, which provide a clearer picture of a portfolio's actual operating costs. An investment in the Portfolio could lose money over short or even long periods. 39 <b>Annual Total Returns — Mid-Cap Index Portfolio</b> 122 213 480 highest return 2009-06-30 0.2018 lowest return 2008-12-31 -0.254 An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. 0.0016 0 The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of its target index and other comparative indexes, which have investment characteristics similar to those of the Portfolio. 0.0003 0.0019 800-522-5555 19 advisors.vanguard.com 61 107 Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. 243 The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. 19 highest return 61 2009-06-30 0.1695 107 lowest return 243 2008-12-31 45 -0.2275 141 246 555 <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000156 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000104 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000106 column period compact * ~</div> 0.1375 0.0614 <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000107 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000136 column period compact * ~</div> -0.4181 0.4037 0.2537 -0.0204 0.1582 0.3493 0.1359 <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000137 column period compact * ~</div> -0.0143 <b>Annual Total Returns — Capital Growth Portfolio</b> -0.0077 -0.0566 -0.0566 0.036 0.0106 0.0106 0.0492 0.0292 0.0179 0.05 An investment in the Portfolio could lose money over short or even long periods. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index, which has investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses, but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. -0.0143 -0.0055 -0.0128 -0.0128 advisors.vanguard.com 800-522-5555 highest return 2009-09-30 0.1443 lowest return 2008-12-31 -0.2164 0.1163 0.1248 0.2675 0.1138 0.1184 0.1158 -0.3036 0.1741 0.3724 -0.4487 0.1308 0.4257 0.1579 -0.1354 0.2014 0.2326 -0.0605 0.078 0.0807 0.0794 -0.0077 -0.0093 0.1547 0.3848 0.1843 0.0262 800-522-5555 Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. advisors.vanguard.com The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of a relevant market index and a comparative index, which have investment characteristics similar to those of the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. An investment in the Portfolio could lose money over short or even long periods. 0.23 41 128 224 505 highest return 2009-06-30 0.2723 lowest return 2008-12-31 -0.2331 0.23 37 116 202 456 An investment in the Portfolio could lose money over short or even long periods. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of the Portfolio’s target index and other comparative indexes, which have investment characteristics similar to those of the Portfolio. 800-522-5555 advisors.vanguard.com <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000144 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000146 column period compact * ~</div> Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000147 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000166 column period compact * ~</div> The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000134 column period compact * ~</div> highest return 2009-09-30 0.2144 lowest return 2008-12-31 -0.2565 <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000124 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000126 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000127 column period compact * ~</div> REIT Index Portfolio Investment Objective The Portfolio seeks to provide a high level of income and moderate long-term capital appreciation by tracking the performance of a benchmark index that measures the performance of publicly traded equity REITs. Fees and Expenses The following table describes the fees and expenses you may pay if you buy and hold shares of the Portfolio. The expenses shown in the table and in the example that follow do not reflect additional fees and expenses associated with the annuity or life insurance program through which you invest. If those additional fees and expenses were included, overall expenses would be higher. Annual Portfolio Operating Expenses<br/><br/>(Expenses that you pay each year as a percentage of the value of your investment) Example The following example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. It illustrates the hypothetical expenses that you would incur over various periods if you invested $10,000 in the Portfolio’s shares. This example assumes that the Portfolio provides a return of 5% each year and that total annual portfolio operating expenses remain as stated in the preceding table. You would incur these hypothetical expenses whether or not you redeem your investment at the end of the given period. Although your actual costs may be higher or lower, based on these assumptions your costs would be: Portfolio Turnover The Portfolio 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. These costs, which are not reflected in annual portfolio operating expenses or in the previous expense example, reduce the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s turnover rate was 21% of the average value of its portfolio. Principal Investment Strategies The Portfolio employs an indexing investment approach designed to track the performance of the MSCI US REIT Index. The Index is composed of stocks of publicly traded equity real estate investment trusts (known as REITs). The Portfolio attempts to replicate the Index by investing all, or substantially all, of its assets in the stocks that make up the Index, holding each stock in approximately the same proportion as its weighting in the Index. Principal Risks An investment in the Portfolio could lose money over short or even long periods. You should expect the Portfolio’s share price and total return to fluctuate within a wide range. The Portfolio is subject to the following risks, which could affect the Portfolio’s performance:<br /><br /> Industry concentration risk, which is the chance that the stocks of REITs will decline because of adverse developments affecting the real estate industry and real property values. Because the Portfolio concentrates its assets in REIT stocks, industry concentration risk is high.<br /><br /> Stock market risk, which is the chance that stock prices overall will decline. Stock markets tend to move in cycles, with periods of rising prices and periods of falling prices. The Portfolio’s target index may, at times, become focused in stocks of a limited number of companies, which could cause the Portfolio to underperform the overall stock market.<br /><br /> Interest rate risk, which is the chance that REIT stock prices overall will decline, and that the cost of borrowing for REITs will increase because of rising interest rates. Interest rate risk is high for the Portfolio.<br /><br /> Investment style risk, which is the chance that returns from REIT stocks—which typically are small- or mid-capitalization stocks—will trail returns from the overall stock market. Historically, REIT stocks have performed quite differently from the overall market.<br /><br /> Derivatives risk. The Portfolio may invest in derivatives, which may involve risks different from, and possibly greater than, those of investments directly in the underlying securities or assets.<br /><br />An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Annual Total Returns The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of its target index and a comparative index, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. Updated performance information is available on our website for Financial Advisors at advisors.vanguard.com or by calling Vanguard toll-free at 800-522-5555. During the periods shown in the bar chart, the highest return for a calendar quarter was 34.45% (quarter ended September 30, 2009), and the lowest return for a quarter was –38.26% (quarter ended December 31, 2008). Average Annual Total Returns for Periods Ended December 31, 2015 0.0024 0 0.0003 0.0027 28 87 152 343 0.38 An investment in the Portfolio could lose money over short or even long periods. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of relevant market indexes, which have investment characteristics similar to those of the Portfolio. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. advisors.vanguard.com 28 800-522-5555 87 highest return 152 2012-03-31 343 0.1812 lowest return 2008-12-31 -0.2154 <b>Annual Total Returns — Growth Portfolio</b> 0.3493 -0.166 -0.3725 0.2914 0.2825 0.0844 0.1746 0.0233 0.3011 0.0222 0.0222 0.0252 0.0252 0.1163 0.1188 0.1188 0.0732 0.0735 0.0753 <b>Annual Total Returns — International Portfolio</b> The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. <b>Annual Total Returns — REIT Index Portfolio</b> 0.21 An investment in the Portfolio could lose money over short or even long periods. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The following bar chart and table are intended to help you understand the risks of investing in the Portfolio. The bar chart shows how the performance of the Portfolio has varied from one calendar year to another over the periods shown. The table shows how the average annual total returns of the Portfolio compare with those of its target index and a comparative index, which have investment characteristics similar to those of the Portfolio. 800-522-5555 advisors.vanguard.com Keep in mind that the Portfolio’s past performance does not indicate how the Portfolio will perform in the future. The Portfolio’s returns are net of its expenses but do not reflect additional fees and expenses that are deducted by the annuity or life insurance program through which you invest. If such fees and expenses were included in the calculation of the Portfolio’s returns, the returns would be lower. highest return 2009-09-30 0.3445 lowest return 2008-12-31 -0.3826 <div style="display:none">~ http://www.vanguard.com/role/ScheduleExpenseExampleTransposed000174 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualTotalReturnsBarChart000176 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAverageAnnualTotalReturnsTransposed000177 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000033 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000043 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000023 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000013 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000053 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000063 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000073 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000083 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000093 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000103 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000113 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000123 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000133 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000143 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000153 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000163 column period compact * ~</div> <div style="display:none">~ http://www.vanguard.com/role/ScheduleAnnualPortfolioOperatingExpenses000173 column period compact * ~</div> Comparative Indexes (reflect no deduction for fees or expenses) Acquired Fund Fees and Expenses are not included in the Portfolio's financial statements, which provide a clearer picture of a portfolio's actual operating costs. Vanguard and the Portfolio's Board have voluntarily agreed to temporarily limit certain net operating expenses in excess of the Portfolio's daily yield so as to maintain a zero or positive yield for the Portfolio. Vanguard and the Portfolio's Board may terminate the temporary expense limitation at any time. Comparative Benchmarks (reflect no deduction for fees or expenses)