(As amended Mar. 1, 1971, eff. July 1, 1971; Mar. 10, 1986, eff. July 1, 1986; Apr. 25, 1989, eff. Dec. 1, 1989; Apr. 30, 1991, eff. Dec. 1, 1991; Apr. 23, 1996, eff. Dec. 1, 1996; Apr. 24, 1998, eff. Dec. 1, 1998; Apr. 29, 2002, eff. Dec. 1, 2002; Apr. 25, 2005, eff. Dec. 1, 2005; Mar. 26, 2009, eff. Dec. 1, 2009; Apr. 28, 2016, eff. Dec. 1, 2016; Apr. 26, 2018, eff. Dec. 1, 2018.)