(Added Apr. 30, 1979, eff. Dec. 1, 1980; amended Pub. L. 99–646, § 12(b), Nov. 10, 1986, 100 Stat. 3594; Mar. 9, 1987, eff. Aug. 1, 1987; Apr. 25, 1989, eff. Dec. 1, 1989; Apr. 30, 1991, eff. Dec. 1, 1991; Apr. 22, 1993, eff. Dec. 1, 1993; Apr. 29, 2002, eff. Dec. 1, 2002; Apr. 25, 2005, eff. Dec. 1, 2005; Apr. 12, 2006, eff. Dec. 1, 2006; Apr. 28, 2010, eff. Dec. 1, 2010.)