"The most significant change in the procedure concerns the actuarial assumptions. Prior procedures required the application to describe the actuarial assumptions used in making projections of the plan's financial status. The revised procedure contains a new Appendix B, 'Information on Actuarial Assumptions and Methods' [which] requires a detailed description of each of the actuarial assumptions used to project the plan's status, including supporting data, the plan's past experience regarding each assumption, and justification of the assumptions in light of the experience."