| | | | 2013 | | 2012 | | 2011 |
| | | | | (in millions) |
| Fixed maturities, available-for-sale | | $ | 10,541 | | $ | 9,800 | | $ | 9,374 |
| Fixed maturities, held-to-maturity | | | 125 | | | 135 | | | 140 |
| Equity securities, available-for-sale | | | 337 | | | 332 | | | 315 |
| Trading account assets | | | 963 | | | 890 | | | 889 |
| Commercial mortgage and other loans | | | 1,985 | | | 2,014 | | | 1,926 |
| Policy loans | | | 611 | | | 597 | | | 598 |
| Short-term investments and cash equivalents | | | 40 | | | 46 | | | 58 |
| Other long-term investments | | | 710 | | | 320 | | | 231 |
| | Gross investment income | | | 15,312 | | | 14,134 | | | 13,531 |
| Less: investment expenses | | | (583) | | | (473) | | | (407) |
| | Net investment income | | $ | 14,729 | | $ | 13,661 | | $ | 13,124 |
