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Investment Information - Net investment income (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Net investment income: |  |  |  |  |
Gross investment income |  | $ 260 | $ 123 | $ 479 | $ 226
Investment expenses |  | (18) | (17) | (38) | (40)
Net investment income |  | 242 | 106 | 441 | 186
Fixed maturities |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income |  | 214 | 105 | 402 | 187
Equity securities |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income |  | 6 | 6 | 10 | 12
Short-term investments |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income |  | 15 | 4 | 29 | 7
Other |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income | [1] | $ 25 | $ 8 | $ 38 | $ 20
[1] | Amounts include dividends and other distributions on investment funds, term loan investments, funds held balances, cash balances and other items.

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