20 See accompanying “Notes to Consolidated Financial Statements.”  Year Ended December 31,  2012  2011 2010 (dollars in thousands) NET INCOME $ 19,039 $ 16,693 $ 13,574 Other comprehensive income, net of tax: Unrealized gains on securities: Unrealized holding gains arising during period 5,854 6,666 1,315 Less: reclassification adjustment for gains included in net income (1,843) (1,940) (1,851) Total unrealized gains on securities 4,011 4,726 (536) Defined benefit pension plans: Pension liability adjustment: Net gain (loss) (2,488) (4,047) 771 Amortization of prior service cost and loss included in net periodic benefit cost  649 380 488 Total pension liability adjustment (1,839) (3,667) 1,259 Other comprehensive income 2,172 1,059 723 Comprehensive income  $ 21,211 $ 17,752 $ 14,297 Consolidated Statements of Comprehensive Income Century Bancorp, Inc. AR ’12