Section, Pub. L. 93–644, § 15, Jan. 4, 1975, 88 Stat. 2329; Pub. L. 94–341, § 3(d), July 6, 1976, 90 Stat. 807, authorized appropriations for fiscal years 1975 through 1977, with possibility of extension for an additional fiscal year and carryover of unobligated funds.