This document contains final regulations relating to the use of actuarial tables in valuing annuities, interests for life or terms of years, and remainder or reversionary interests. These regulations will effect the valuation of inter vivos and testamentary transfers of interests dependent on one or more measuring lives. Section 7520 of the Internal Revenue Code of 1986 (Code) was enacted by section 5031 of the Technical and Miscellaneous Revenue Act of 1988 and was effective on May 1, 1989. These regulations are necessary because section 7520(c)(3) directs the Secretary to revise the actuarial tables used in valuing interests dependent on mortality experience not less frequently than once each 10 years to take into account the most recent mortality experience available as of the time of the revision. This document contains amendments to the regulations revising certain tables used for the valuation of partial interests in property under section 7520 to reflect the most recent mortality experience available.