loss on the contract may be recorded , if necessary , and any remaining deferred implementation revenues would typically be recognized over the remaining service period through the termination date . in connection with our long-term outsourcing service agreements , highly customized implementation efforts are often necessary to set up clients and their human resource or benefit programs on our systems and operating processes . for outsourcing services sold separately or accounted for as a separate unit of accounting , specific , incremental and direct costs of implementation incurred prior to the services commencing are generally deferred and amortized over the period that the related ongoing services revenue is recognized . deferred costs are assessed for recoverability on a periodic basis to the extent the deferred cost exceeds related deferred revenue . pensions we sponsor defined benefit pension plans throughout the world . our most significant plans are located in the u.s. , the u.k. , the netherlands and canada . our significant u.s. , u.k. , netherlands and canadian pension plans are closed to new entrants . we have ceased crediting future benefits relating to salary and service for our u.s. , u.k. , netherlands and canadian plans to the extent statutorily permitted . in 2016 , we estimate pension and post-retirement net periodic benefit cost for major plans to increase by $ 15 million to a benefit of approximately $ 54 million . the increase in the benefit is primarily due to a change in our approach to measuring service and interest cost . effective december 31 , 2015 and for 2016 expense , we have elected to utilize a full yield curve approach in the estimation of the service and interest cost components of net periodic pension and post-retirement benefit cost for our major pension and other post-retirement benefit plans by applying the specific spot rates along the yield curve used in the determination of the benefit obligation to the relevant projected cash flows . in 2015 and prior years , we estimated these components of net periodic pension and post-retirement benefit cost by applying a single weighted-average discount rate , derived from the yield curve used to measure the benefit obligation at the beginning of the period . we have made this change to improve the correlation between projected benefit cash flows and the corresponding yield curve spot rates and to provide a more precise measurement of service and interest costs . this change does not affect the measurement of the projected benefit obligation as the change in the service cost and interest cost is completely offset in the actuarial ( gain ) loss recorded in other comprehensive income . we accounted for this change as a change in estimate and , accordingly , will account for it prospectively . recognition of gains and losses and prior service certain changes in the value of the obligation and in the value of plan assets , which may occur due to various factors such as changes in the discount rate and actuarial assumptions , actual demographic experience and/or plan asset performance are not immediately recognized in net income . such changes are recognized in other comprehensive income and are amortized into net income as part of the net periodic benefit cost . unrecognized gains and losses that have been deferred in other comprehensive income , as previously described , are amortized into compensation and benefits expense as a component of periodic pension expense based on the average life expectancy of the u.s. , the netherlands , canada , and u.k . plan members . we amortize any prior service expense or credits that arise as a result of plan changes over a period consistent with the amortization of gains and losses . as of december 31 , 2015 , our pension plans have deferred losses that have not yet been recognized through income in the consolidated financial statements . we amortize unrecognized actuarial losses outside of a corridor , which is defined as 10% ( 10 % ) of the greater of market-related value of plan assets or projected benefit obligation . to the extent not offset by future gains , incremental amortization as calculated above will continue to affect future pension expense similarly until fully amortized . the following table discloses our unrecognized actuarial gains and losses , the number of years over which we are amortizing the experience loss , and the estimated 2016 amortization of loss by country ( amounts in millions ) : .
in 2015 what was the ratio of the unrecognized prior service cost to the income
the unrecognized prior service cost ( income ) at december 31 , 2015 was $ 9 million , $ 46 million , and $ ( 7 ) million in the u.s. , u.k . and other plans , respectively . for the u.s . pension plans we use a market-related valuation of assets approach to determine the expected return on assets , which is a component of net periodic benefit cost recognized in the consolidated statements of income . this approach .