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v3.23.2

Investments (Tables) | 6 Months Ended
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Jun. 30, 2023
Investments |
Summary of amortized cost and fair value of the trust investments | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | Amortized Costs | ​ | Fair Values
​ | ​ | Longest | ​ | June 30, | ​ | December 31, | ​ | June 30, | ​ | December 31,
(in millions) |  | Maturity Dates |  | 2023 |  | 2022 |  | 2023 |  | 2022
Municipal bonds |  | 2061 |  | $ | 617 |  | $ | 672 | ​ | $ | 704 | ​ | $ | 754
Government and agency securities |  | 2073 |  | ​ | 1,151 |  | ​ | 1,025 | ​ |  | 1,222 | ​ |  | 1,091
Corporate bonds |  | 2070 |  | ​ | 386 |  | ​ | 351 | ​ |  | 414 | ​ |  | 377
Short-term investments and receivables/payables1 |  | One-year |  | ​ | 146 |  | ​ | 110 | ​ |  | 154 | ​ |  | 116
Total debt securities and other | ​ | ​ | ​ | $ | 2,300 | ​ | $ | 2,158 | ​ | ​ | 2,494 | ​ | ​ | 2,338
Equity securities |  | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 1,632 | ​ | ​ | 1,610
Total |  |  | ​ | ​ | ​ | ​ | ​ | ​ | ​ | $ | 4,126 | ​ | $ | 3,948
1 | Short-term investments included $9 million and $41 million of repurchase agreements payable by financial institutions which earn interest, were fully and 97% secured by U.S. Treasury securities and mature by July 3, 2023 and January 3, 2023 as of June 30, 2023 and December 31, 2022, respectively.
Summary of gains and losses | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three months ended June 30, | ​ | Six months ended June 30,
(in millions) |  | 2023 |  | 2022 |  | 2023 |  | 2022
Gross realized gains | ​ | $ | 124 | ​ | $ | 74 | ​ | $ | 195 | ​ | $ | 89
Gross realized losses | ​ |  | (8) | ​ |  | (45) | ​ |  | (31) | ​ |  | (61)
Net unrealized (losses)/gains for equity securities | ​ |  | (11) | ​ |  | (332) | ​ |  | 64 | ​ |  | (432)

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