82 CIGNA CORPORATION -  2012 Form  10-K PART II ITEM 8 Financial Statements and Supplementary Data Incurred but not yet reported comprises the majority of the reserve balance as follows: Reinsurance and other amounts recoverable reflect amounts due from reinsurers and policyholders to cover incurred but not reported and pending claims for minimum premium products and certain administrative services only business where the right of offset does not exist. See Note 8 for additional information on reinsurance. For the year ended December 31, 2012, actual experience differed from the Company’s key assumptions resulting in favorable incurred claims related to prior years’ medical claims payable of $200 million, or 2.2% of the current year incurred claims as reported for the year ended December 31, 2011. Actual completion factors accounted for $91 million, or 1.0% of the favorability, while actual medical cost trend resulted in the remaining $109 million, or 1.2%. actuarial standards of practice, that require the liabilities be adequate under moderately adverse conditions. As the Company establishes the liability for each incurral year, the Company ensures that its assumptions appropriately consider moderately adverse conditions. When a portion of the development related to the prior year incurred claims is offset by an increase determined appropriate to address moderately adverse conditions for the current year incurred claims, the Company does not consider that offset amount as having any impact on shareholders’ net income. Second, as a result of the adoption of the commercial minimum medical loss ratio (MLR) provisions of the Patient Protection and Affordable Care Act in 2011, changes in medical claim estimates due to prior year development may be partially offset by a change in the MLR rebate accrual. For the year ended December 31, 2011, actual experience differed from the Company’s key assumptions, resulting in favorable incurred claims related to prior years’ medical claims payable of $140 million, or 1.5% of the current year incurred claims as reported for the year ended December 31, 2010. Actual completion factors resulted in $96 million, or 1.0% of the favorability, while actual medical cost trend resulted in the remaining $44 million, or 0.5%. The corresponding impact of prior year development on shareholders’ net income was $66 million for the year ended December 31, 2012 compared with $49 million for the year ended December 31, 2011. The favorable effects of prior year development on net income in 2012 and 2011 primarily reflect low medical services utilization trend. The change in the amount of the incurred claims related to prior years in the medical claims payable liability does not directly correspond to an increase or decrease in the Company’s shareholders’ net income recognized for the following reasons. First, the Company consistently recognizes the actuarial best estimate of the ultimate liability within a level of confidence, as required by Third, changes in reserves for the Company’s retrospectively experience-rated business do not always impact shareholders’ net income. For the Company’s retrospectively experience-rated business only adjustments to medical claims payable on accounts in deficit affect shareholders’ net income. An increase or decrease to medical claims payable on accounts in deficit, in effect, accrues to the Company and directly impacts shareholders’ net income. An account is in deficit when the accumulated medical costs and administrative charges, including profit charges, exceed the accumulated premium received. Adjustments to medical claims payable on accounts in surplus accrue directly to the policyholder with no impact on the Company’s shareholders’ net income. An account is in surplus when the accumulated premium received exceeds the accumulated medical costs and administrative charges, including profit charges. Activity in medical claims payable was as follows: (In millions) 2012 2011 Incurred but not yet reported $ 1,541 $ 1,059 Reported claims in process 243 232 Other medical expense payable 72 14 MEDICAL CLAIMS PAYABLE $ 1,856 $ 1,305 (In millions) 2012 2011 2010 Balance at January 1, $ 1,305 $ 1,400 $ 1,045 Less: Reinsurance and other amounts recoverable 249 284 257 Balance at January 1, net 1,056 1,116 788 Acquired net: 504 - - Incurred claims related to: Current year 14,428 9,265 9,337 Prior years (200) (140) (115) Total incurred 14,228 9,125 9,222 Paid claims related to: Current year 12,854 8,227 8,217 Prior years 1,320 958 677 Total paid 14,174 9,185 8,894 Balance at December 31, net 1,614 1,056 1,116 Add: Reinsurance and other amounts recoverable 242 249 284 Balance at December 31, $ 1,856 $ 1,305 $ 1,400