LIMITATION ON CHANGES IN CURRENT LIABILITY ASSUMPTIONS.

SEC. 752. LIMITATION ON CHANGES IN CURRENT LIABILITY ASSUMPTIONS. (a) In General.— Paragraph (5) of section 412(c) is amended— (1) by striking “If the funding method” and inserting the following: “(A) In general.—If the funding method”, and (2) by adding at the end the following new subparagraph: “(B) Approval required for certain changes in assumptions by certain single-employer plans subject to additional funding requirement.— “(i) In general.—No actuarial assumption (other than the assumptions described in subsection (1)(7)(C)) used to determine the current liability for a plan to which this subparagraph applies may be changed without the approval of the Secretary. “(ii) Plans to which subparagraph applies.— This subparagraph shall apply to a plan only if— “(I) the plan is a defined Benefit plan (other than a multiemployer plan) to which title IV of the Employee Retirement Income Security Act of 1974 applies; “(II) the aggregate unfunded vested benefits as of the close of the preceding plan year (as determined under section 4006(a)(3)(E)(iii) of the Employee Retirement Income Security Act of 1974) of such plan and all other plans maintained by the contributing sponsors (as defined in section 4001(a)(13) of such Act) and members of such sponsors’ controlled groups (as defined in section 108 STAT. 50234001(a)(14) of such Act) which are covered by title IV of such Act (disregarding plans with no unfunded vested benefits) exceed $50,000,000; and “(III) the change in assumptions (determined after taking into account any changes in interest rate and mortality table) results in a decrease in the unfunded current liability of the plan for the current plan year that exceeds $50,000,000, or that exceeds $5,000,000 and that is 5 percent or more of the current liability of the plan before such change.” (b) Effective Date — (1) In general.—The amendment made by this section shall apply to changes in assumptions for plan years beginning after October 28, 1993. (2) Certain changes cease to be effective.— In the case of changes in assumptions for plan years beginning after December 31, 1992, and on or before October 28, 1993, such changes shall cease to be effective for plan years beginning after December 31, 1994, if— (A) such change would have required the approval of the Secretary of the Treasury had such amendment applied to such change, and (B) such change is not so approved.