Table of Contents Our overall expected long-term rate of return on assets for the pension trust fund is 7.5% as of January 1, 2020, which is both a pre-tax and after-tax rate as pension funds are generally not subject to income tax. Our overall expected long-term rate of return on assets for the other post- retirement benefits trust, on an after-tax basis, is 6.00% as of January 1, 2020. The expected returns on investments in the pension trust and the other post-retirement benefits trust are based upon the target asset allocations for the two trusts. Our accrued post-retirement benefit liability and the service and interest components of the related net periodic benefit costs are calculated using an actuarial assumption regarding health care cost inflation. For measurement purposes, a 5.75%, 6.75%, 4.5% and 7.0% annual rate of increase in the per capita cost of covered health care benefits was assumed for 2020 for pre-65 medical, pre-65 drug, post-65 medical and post-65 drug, respectively. The health care cost trend rates are assumed to decline steadily to an ultimate rate of 4.5% by 2025 for pre-65 medical and by 2026 for pre-65 and post-65 drug. Post-65 medical trend is assumed to be 4.5% for all years into the future. Assumed health care cost trend rates have a significant effect on the amounts reported for the health care plan. The estimated rate of compensation increase used in our retirement plans is 4.5% and is based on recent trends for all non-union employees and the amounts we are contractually obligated for union employees. The following table reflects the sensitivities that a change in certain actuarial assumptions would have had on the December 31, 2019 reported pension liability and our 2019 reported pension expense (in thousands): Increase (Decrease) Actuarial Assumption Impact on Pension Liability Impact on Pension Expense Discount rate: Increase 1% $ (52,113) $ (3,502) Decrease 1% 64,869 4,483 Expected long-term rate of return on plan assets: Increase 1% N/A (2,762 ) Decrease 1% N/A 2,762 Compensation rate: Increase 1% 10,105 1,632 Decrease 1% (9,051 ) (1,268 ) The following chart reflects the sensitivities that a change in certain actuarial assumptions would have had on the December 31, 2019 other post-retirement benefit obligation and our 2019 reported other post-retirement benefit expense (in thousands): Increase (Decrease) Actuarial Assumption Impact on Other Post-retirement Benefit Obligation Impact on Other Post-retirement Benefit Expense Impact on Other Post-retirement Service and Interest Cost Discount rate: Increase 1% $ (9,231) $ (997) $ (321) Decrease 1% 11,970 1,288 420 Healthcare cost trend rate: Increase 1% 10,641 1,758 1,027 Decrease 1% (8,325) (1,358) (778) Expected long-term rate of return on plan assets: Increase 1% N/A (354) N/A Decrease 1% N/A 354 N/A 27