M & K Employee Solutions, LLC v. Trustees of the IAM National Pension Fund

Question Presented

Whether 29 U.S.C. § 1391's instruction to compute withdrawal liability "as of the end of the plan year" requires the plan to base the computation on the actuarial assumptions most recently adopted before the end of the year, or allows the plan to use different actuarial assumptions that were adopted after, but based on information available as of, the end of the year.