Notes to Consolidated Financial Statements continued Thousands of Georgian Lari 13. Goodwill continued Discount rates Discount rates reflect management’s estimate of return required in each business. This is the benchmark used by management to assess operating performance and to evaluate future investment proposals. Discount rates are calculated by using pre-tax weighted average cost of capital (“WACC”). For the Retail and Corporate Banking CGUs the following additional assumptions were made: •stable, business as usual growth of loans and deposits; •no material changes in cost/income structure or ratio; •stable, business as usual growth of trade finance and other documentary businesses; and •further expansion of the Express Banking businesses bringing more stable margins to Retail Banking. Sensitivity to changes in assumptions Management believes that reasonable possible changes to key assumptions used to determine the recoverable amount for each CGU will not result in an impairment of goodwill. The excess of value-in-use over carrying value is determined by reference to the net book value as at 31 December 2018. Possible change was taken as +/-1% in discount rate and growth rate. 14. Taxation The corporate income tax credit (expense) comprises: 2018 2017 2016 Current income expense (39,169) (42,396) (25,034) Deferred income tax credit (expense) (18,682) 9,669 63,690 Income tax (expense) credit (57,851) (32,727) 38,656 Income tax (expense) benefit attributable to continuing operations (56,665) (26,592) 26,444 Income tax (expense) benefit attributable to a discontinued operation (Note 5) (1,186) (6,135) 12,212 Deferred income tax expense in other comprehensive income (265) (1,328) (2,274) Deferred tax related to items charged or credited to other comprehensive income during the years ended 31 December 2018, 2017 and 2016 was as follows: 2018 2017 2016 Currency translation differences – (576) (2,253) Net losses on investment securities (265) 27 (21) Revaluation of buildings – (779) – Income tax expense in other comprehensive income (265) (1,328) (2,274) The income tax rate applicable to most of the Group’s income is the income tax rate applicable to subsidiaries’ income which ranges from 15% to 27% (2017: from 15% to 27%, 2016: from 15% to 27%). 236 Annual Report 2018Bank of Georgia Group PLC