153 2.22 Assets and liabilities relating to employee benefits Changes in accounting policy a. Short-term employee benefits b. Post-employment benefits  Defined contribution plans Defined benefit plans Measurement Profit or loss recognition Remeasurements of the net defined benefit liability (asset) which is recognized in other comprehensive income are revisited quarterly.  Remeasurements of the net defined benefit liability (asset) shall not be reclassified to profit or loss in a subsequent period. Any employee contributions are deducted from the current year service cost. Net interest on the net defined benefit liability (asset)  shall be determined by multiplying the net defined benefit liability (asset) by the applicable discount rate. Net interest on the net  Under the revised IAS 19, the cost of the plans are determined at the beginning of the year and comprise the following components: Prior to January 1, 2013, Aegon determined the cost of the plans at the beginning of the year, based on the prevalent actuarial  assumptions, discount rate and expected return on plan assets. Changes in assumptions, discount rate and experience adjustments  were not charged to the income statement in the period in which they occur, but were deferred. Unrecognized actuarial gains and losses  were amortized in a straight line over the average remaining working life of the employees covered by the plan, to the extent that  the gains or losses exceeded the corridor limits. The corridor was defined as ten percent of the greater of the defined benefit obligation  or the plan assets. Plan assets are qualifying insurance policies and assets held by long-term employee benefit funds that can only be used to pay  the employee benefits under the plan and are not available to the Group’s creditors. They are measured at fair value and are deducted  in determining the amount recognized on the statement of financial position. The defined benefit obligation is based on the terms and conditions of the plan applicable on the balance sheet date. In measuring  the defined benefit obligation the Group uses the projected unit credit method and actuarial assumptions that represent the best  estimate of future variables. The benefits are discounted using an interest rate based on the market yields for high-quality corporate  bonds on the balance sheet date. Prior to January 1, 2013, Aegon charged plan improvements directly to the income statement, unless  they were conditional on the continuation of employment. In that case, the related cost was deducted from the liability as past service  cost and amortized over the vesting period. Under the revised IAS 19, plan improvements (either vested or unvested) are recognized in  the income statement at the date when the plan improvement occurs. The contribution payable to a defined contribution plan for services provided is recognized as an expense in the income statement.  An asset is recognized to the extent that the contribution paid exceeds the amount due for services provided. The Group has issued defined contribution plans and defined benefit plans. A plan is classified as a defined contribution plan when  the Group has no further obligation than the payment of a fixed contribution. All other plans are classified as defined benefit plans. Prior to January 1, 2013, short-term benefits were recognized based on the employee's entitlement to the benefits. Under  the revised IAS 19 a liability is recognized for the undiscounted amount of short-term employee benefits expected to be settled  within one year after the end of the period in which the service was rendered. Accumulating short-term absences are recognized  over the period in which the service is provided. Benefits that are not service-related are recognized when the event that gives rise to  the obligation occurs. Aegon has applied the new policy for employee benefits on or after January 1, 2011, in accordance with the transitional provisions  of the revised IAS 19. Aegon's accounting policy for assets and liabilities relating to employee benefits as set out below reflects  the changes under the revised IAS 19. Aegon adopted IAS 19 - Employee Benefits, on January 1, 2013. This resulted in the Group changing its accounting policy for the assets  and liabilities relating to employee benefits.  ■ Current year service cost which is recognized in profit or loss; and ■ Net interest on the net defined benefit liability (asset) which is recognized in profit or loss; 