Table of Contents Specialty - Medical Professional Liability Cumulative Net Incurred Claim and Allocated Claim Adjustment Expenses are presented in the following table. Cumulative Net Paid Claims and Allocated Claim Adjustment Expenses are presented in the following table. Net strengthening or (releases) of prior accident year reserves is presented in the following table. (1) Data presented for these calendar years is required supplemental information, which is unaudited. 94 As of December 31 Calendar Year As of December 31, 2018 (In millions, except reported claims data) 2009 (1) 2010 (1) 2011 (1) 2012 (1) 2013 (1) 2014 (1) 2015 (1) 2016 (1) 2017 (1) 2018 IBNR Cumulative Number of Claims Accident Year 2009 $ 389 $ 390 $ 392 $ 392 $ 366 $ 346 $ 336 $ 309 $ 302 $ 310 $ — 14,716 2010 402 412 423 426 415 395 365 360 356 — 14,615 2011 429 437 443 468 439 434 437 437 8 16,505 2012 464 469 508 498 493 484 493 10 17,691 2013 462 479 500 513 525 535 28 19,442 2014 450 489 537 530 535 30 19,602 2015 433 499 510 494 78 17,835 2016 427 487 485 120 15,427 2017 412 449 217 13,777 2018 404 333 11,205 Total $ 4,498 $ 824 As of December 31 Calendar Year (In millions) 2009 (1) 2010 (1) 2011 (1) 2012 (1) 2013 (1) 2014 (1) 2015 (1) 2016 (1) 2017 (1) 2018 Accident Year 2009 $ 9 $ 63 $ 143 $ 211 $ 247 $ 269 $ 280 $ 288 $ 291 $ 300 2010 10 86 173 257 306 326 337 346 350 2011 17 109 208 295 347 375 398 409 2012 14 117 221 323 388 427 457 2013 17 119 255 355 414 462 2014 23 136 258 359 417 2015 22 101 230 313 2016 18 121 246 2017 19 107 2018 21 Total $ 3,082 Net liability for unpaid claim and allocated claim adjustment expenses for the accident years presented $ 1,416 Net liability for unpaid claim and claim adjustment expenses for accident years prior to 2009 18 Liability for unallocated claim adjustment expenses for accident years presented 23 Total net liability for unpaid claim and claim adjustment expenses $ 1,457 For the years ended December 31 Calendar Year (In millions) 2010 (1) 2011 (1) 2012 (1) 2013 (1) 2014 (1) 2015 (1) 2016 (1) 2017 (1) 2018 Total Accident Year 2009 $ 1 $ 2 $ — $ (26) $ (20) $ (10) $ (27) $ (7) $ 8 $ (79) 2010 10 11 3 (11 ) (20 ) (30 ) (5 ) (4 ) (46 ) 2011 8 6 25 (29) (5) 3 — 8 2012 5 39 (10 ) (5 ) (9 ) 9 29 2013 17 21 13 12 10 73 2014 39 48 (7 ) 5 85 2015 66 11 (16) 61 2016 60 (2 ) 58 2017 37 37 Total net development for the accident years presented above 60 58 47 Total net development for accident years prior to 2009 (51) (21) 1 Total unallocated claim adjustment expense development — (7 ) (1 ) Total $ 9 $ 30 $ 47