Table of Contents The following tables present the estimated fair value and gross unrealized losses of fixed maturity and equity securities in a gross unrealized loss position by the length of time in which the securities have continuously been in that position. (1) As of January 1, 2018, the Company adopted ASU 2016-01,  Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities . The change in fair value of equity securities is now recognized through the income statement. See Note A to the Consolidated Financial Statements for additional information. 74 Less than 12 Months 12 Months or Longer Total December 31, 2017 Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 1,354 $ 21 $ 168 $ 7 $ 1,522 $ 28 States, municipalities and political subdivisions 72 1 85 1 157 2 Asset-backed: Residential mortgage-backed 1,228 5 947 27 2,175 32 Commercial mortgage-backed 403 4 212 10 615 14 Other asset-backed 248 3 18 2 266 5 Total asset-backed 1,879 12 1,177 39 3,056 51 U.S. Treasury and obligations of government-sponsored enterprises 49 2 21 2 70 4 Foreign government 166 2 4 — 170 2 Total fixed maturity securities available-for-sale 3,520 38 1,455 49 4,975 87 Equity securities available-for-sale: Common stock 7 1 — — 7 1 Preferred stock 93 1 — — 93 1 Total equity securities available-for-sale 100 2 — — 100 2 Total $ 3,620 $ 40 $ 1,455 $ 49 $ 5,075 $ 89 Less than 12 Months 12 Months or Longer Total December 31, 2018  (1) Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Fixed maturity securities available-for-sale: Corporate and other bonds $ 8,543 $ 340 $ 825 $ 55 $ 9,368 $ 395 States, municipalities and political subdivisions 517 8 5 1 522 9 Asset-backed: Residential mortgage-backed 1,932 23 1,119 34 3,051 57 Commercial mortgage-backed 728 10 397 22 1,125 32 Other asset-backed 834 21 125 3 959 24 Total asset-backed 3,494 54 1,641 59 5,135 113 U.S. Treasury and obligations of government-sponsored enterprises 21 — 19 — 40 — Foreign government 114 2 124 2 238 4 Total $ 12,689 $ 404 $ 2,614 $ 117 $ 15,303 $ 521