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Investment Information - Net investment income (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Net investment income: |  |  |  |  |
Gross investment income |  | $ 422 | $ 289 | $ 1,158 | $ 768
Investment expenses |  | (23) | (20) | (68) | (58)
Net investment income |  | 399 | 269 | 1,090 | 710
Fixed maturities |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income |  | 340 | 243 | 926 | 645
Short-term investments |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income |  | 38 | 19 | 102 | 48
Equity securities |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income |  | 9 | 5 | 27 | 15
Other |  |  |  |  |
Net investment income: |  |  |  |  |
Gross investment income | [1] | $ 35 | $ 22 | $ 103 | $ 60
[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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