at the end of 2015 , the company changed the approach used to measure service and interest costs for its u.s . and material international pension and other postretirement benefits . for 2016 , the company elected to measure service and interest costs by applying the specific spot rates along that yield curve to the plans 2019 liability cash flows . the company believes this approach provides a more precise measurement of service and interest costs by aligning the timing of the plans 2019 liability cash flows to the corresponding spot rates on the yield curve . for 2015 , the company measured service and interest costs utilizing a single weighted-average discount rate derived from the yield curve used to measure the plan obligations . the change in approach did not affect the measurement of the company 2019s plan obligations or the funded status . the company has accounted for this change as a change in accounting estimate and , accordingly , has accounted for it on a prospective basis . the expected long-term rate of return used for the u.s . plans is based on the pension plan 2019s asset mix . the company considers expected long-term real returns on asset categories , expectations for inflation , and estimates of the impact of active management of the assets in coming to the final rate to use . the company also considers actual historical returns . the expected long-term rate of return used for the company 2019s international plans is determined in each local jurisdiction and is based on the assets held in that jurisdiction , the expected rate of returns for the type of assets held and any guaranteed rate of return provided by the investment . the other assumptions used to measure the international pension obligations , including discount rate , vary by country based on specific local requirements and information . as previously noted , the measurement date for these plans is november 30 . the company uses most recently available mortality tables as of the respective u.s . and international measurement dates . for postretirement benefit measurement purposes as of december 31 , 2016 , the annual rates of increase in the per capita cost of covered health care were assumed to be 6.75% ( 6.75 % ) for pre-65 costs and 7.25% ( 7.25 % ) for post-65 costs . the rates are assumed to decrease each year until they reach 5% ( 5 % ) in 2023 and remain at those levels thereafter . health care costs for certain employees which are eligible for subsidy by the company are limited by a cap on the subsidy . during the third quarter of 2016 , the compensation committee of the company 2019s board of directors approved moving the u.s . postretirement healthcare plans to a retiree exchange approach , rather than the employee group waiver plan plus wrap program , for post-65 retiree medical coverage beginning in 2018 , and the company informed all eligible legacy ecolab and legacy nalco retirees of the change . as a result of the approval and communication to the beneficiaries , the ecolab and nalco plans were re-measured , resulting in a $ 50 million reduction of postretirement benefit obligations , with a corresponding impact to aoci of $ 31 million , net of tax . the remeasurement was completed using discount rates of 3.29% ( 3.29 % ) and 3.60% ( 3.60 % ) , respectively . additionally , at the time of this remeasurement , the nalco u.s . postretirement health care plan was merged with the ecolab u.s . postretirement health care plan . as a result of these actions , the company 2019s u.s . postretirement health care costs decreased by $ 5 million in 2016 . assumed health care cost trend rates have an effect on the amounts reported for the company 2019s u.s . postretirement health care benefits plan . a one-percentage point change in the assumed health care cost trend rates would have the following effects: .
for the ecolab and nalco plan remeasurement , what percentage in the reduction of postretirement benefit obligations created a corresponding impact to aoci?
plan asset management the company 2019s u.s . investment strategy and policies are designed to maximize the possibility of having sufficient funds to meet the long-term liabilities of the pension fund , while achieving a balance between the goals of asset growth of the plan and keeping risk at a reasonable level . current income is not a key goal of the policy . the asset allocation position reflects the company 2019s ability and willingness to accept relatively more short-term variability in the performance of the pension plan portfolio in exchange for the expectation of better long-term returns , lower pension costs and better funded status in the long run . the pension fund is diversified across a number of asset classes and securities . selected individual portfolios within the asset classes may be undiversified while maintaining the diversified nature of total plan assets . the company has no significant concentration of risk in its u.s . plan assets . assets of funded retirement plans outside the u.s . are managed in each local jurisdiction and asset allocation strategy is set in accordance with local rules , regulations and practice . therefore , no overall target asset allocation is presented . although non-u.s . equity securities are all considered international for the company , some equity securities are considered domestic for the local plan . the funds are invested in a variety of equities , bonds and real estate investments and , in some cases , the assets are managed by insurance companies which may offer a guaranteed rate of return . the company has no significant concentration of risk in its international plan assets . the fair value hierarchy is used to categorize investments measured at fair value in one of three levels in the fair value hierarchy . this categorization is based on the observability of the inputs used in valuing the investments . see note 7 for definitions of these levels. .