From last 10k
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We have significant pension and other postretirement benefit funding obligations, which may adversely affect our liquidity, results of operations and financial condition.
Our pension funding obligations are significant. The amount of these obligations will depend on the performance of investments held in trust by the pension plans, interest rates for determining liabilities and actuarial experience. The minimum funding obligation applicable to our pension plans was subject to favorable temporary funding rules that expired at the end of 2017. Our minimum pension funding obligations are likely to increase materially beginning in 2019, when we will be required to make cash contributions corresponding to determinations made regarding the 2018 fiscal year. In addition, we may have significant obligations for other postretirement benefits, the ultimate amount of which depends on, among other things, the outcome of an adversary proceeding related to retiree medical and other postretirement benefits and life insurance obligations filed in the Chapter 11 Cases.”