(As amended Dec. 27, 1948, eff. Oct. 20, 1949; Feb. 28, 1966, eff. July 1, 1966; Apr. 24, 1972, eff. Oct. 1, 1972; Apr. 22, 1974, eff. Dec. 1, 1975; Pub. L. 94–64, § 3(29), July 31, 1975, 89 Stat. 375; Apr. 30, 1979, eff. Dec. 1, 1980; Mar. 9, 1987, eff. Aug. 1, 1987; Apr. 22, 1993, eff. Dec. 1, 1993; Apr. 29, 2002, eff. Dec. 1, 2002; Apr. 23, 2008, eff. Dec. 1, 2008.)