Money market funds are classified as cash equivalents and investments in fixed income securities are classified as available-for-sale in the consolidated balance sheets. Available-for-sale fixed income securities are recorded at their estimated fair value. The amortized cost, gross unrealized holding gains and losses included in other comprehensive income and the fair value of the available-for-sale fixed income securities at June 30, 2023 and December 31, 2022 are presented in the tables below.

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The Company invests in highly rated investment grade debt securities. All of the Company’s available-for-sale securities have final maturities of one year or less. The Company reviews the individual securities that have unrealized losses on a regular basis. The Company evaluates whether it has the intention to sell any of these investments and whether it is more likely than not that it will be required to sell any of them before recovery of the amortized cost basis. Neither of these criteria were met as of June 30, 2023 or December 31, 2022. The Company additionally evaluates whether the decline in fair value of the securities below their amortized cost basis is related to credit losses or other factors. Based on this evaluation, the Company determined that the unrealized losses for its available-for-sale securities were primarily attributable to changes in interest rates and non-credit-related factors. Accordingly, the Company determined that none of the unrealized losses were other-than-temporary, and that recognition of an impairment charge was not required as of June 30, 2023 or December 31, 2022. As of June 30, 2023, there were 14 securities that were in an unrealized loss position with a market value of $64.6 million, with the largest loss for any single security being inconsequential. None of the Company’s available-for-sale securities have been in an unrealized loss position for more than one year. No available-for-sale securities were sold in the three and six months ended June 30, 2023 or the three and six months ended June 30, 2022.

See Note 8 for additional information regarding the fair value of the Company’s available-for-sale securities.