The following table presents the change in the balance of goodwill: The recoverable amounts used in goodwill impairment testing are calculated using discounted cash flow models based on the  following significant unobservable inputs: The major components of income tax expense for the years ended December 31, 2013 and December 31, 2012 are set out below: 15.  INCOME TAXES YEARS ENDED DECEMBER 31  (MILLIONS) 2013 2012 Cost at beginning of year  $ 2,540 $ 2,652 Acquisitions through business combinations  — 60 Disposals  (645) (101) Foreign currency translation and other  (257) (71) Cost at end of year  $ 1,638 $ 2,540 The following table reconciles accumulated impairment losses: YEARS ENDED DECEMBER 31  (MILLIONS) 2013 2012 Accumulated impairment at beginning of year  $ (50) $ (45) Impairment losses  — (5) Accumulated impairment at end of year  $ (50) $ (50) The following table presents goodwill by geography: (MILLIONS) Dec. 31, 2013 Dec. 31, 2012 United States  $ 230 $ 819 Canada  56 57 Australia  861 1,052 Brazil  397 518 Europe  27 28 Other  17 16 $ 1,588 $ 2,490 Valuation technique Significant unobservable input(s) Relationship of unobservable input(s) to fair value Discounted cash flow models • Future cash flows • Increases (decreases) in future cash flows will  increase (decrease) the recoverable amount • Discount rate • Increases (decreases) in discount rate will decrease  (increase) the recoverable amount • Terminal capitalization rate • Increases (decreases) in terminal  capitalization rate  will decrease (increase) the recoverable amount • Exit date • Increases (decreases) in the exit date will decrease  (increase) the recoverable amount YEARS ENDED DECEMBER 31  (MILLIONS) 2013 2012 Current income taxes  $ 159 $ 135 Deferred income tax expense/(recovery) Origination and reversal of temporary differences  871 479 Recovery arising from previously unrecognized tax assets  (130) (93) Change of tax rates and imposition of new legislation  (55) (2) Total deferred income taxes  686 384 Income taxes  $ 845 $ 519 2013 ANNUAL REPORT 127