19. Retirement Benefit Plans (continued)  (Cdn$ in millions) 2012 2011 Defined Non-Pension Defined Non-Pension  Benefit Post- Benefit Post-  Pension Retirement Pension Retirement  Plans  Benefit Plans  Plans  Benefit Plans Actuarial losses  $ 63 $ 43 $ 182 $ 1 Total amount recognized in other comprehensive income  63 43 182 1 Total cumulative amount recognized in retained earnings  $ 316 $ 92 $ 253 $ 49 The amounts recognized in other comprehensive income during the year are as follows: A 1% change in the initial and ultimate medical trend rate assumptions would have the following effect on our post- retirement obligations and expense: 2012 2011 Increase  Increase  (Decrease) in Increase (Decrease) in Increase Service and (Decrease) in Service and (Decrease) in  (Cdn$ in millions) Interest Cost  Obligation Interest Cost  Obligation  Effect of 1% increase in medical trend rate  $ 6 $ 87 $ 5 $ 67 Effect of 1% decrease in medical trend rate  (4) (68) (4) (52) The assets of our defined benefit pension plans are managed by pension asset fund managers under the oversight of  the Teck Resources Limited Executive Pension Committee. Our pension plan investment strategies support the objectives of each defined benefit plan and are related to the plan  demographics and timing of expected benefit payments to plan members. The objective for the plan asset portfolios is  to achieve annual portfolio returns over a four-year period in excess of the annual percentage change in the Consumer  Price Index plus a certain premium. To achieve this objective, a strategic asset allocation policy has been developed for each defined benefit plan. The asset  allocation is monitored quarterly and rebalanced if the funds in an asset class exceed their allowable allocation ranges.  We review the investment guidelines for each plan at least annually, and the portfolio and investment managers’  performance is monitored quarterly. Teck 2012 Annual Report 112 Notes to Consolidated Financial Statements  Years ended December 31, 2012 and 2011 e) Health Care Sensitivity f) Investment of Plan Assets