1986 March 16 1989 February 26 1993 January 29 1994 March 18 1995 May 19 1996 May 24 2002 April 19 2002 November 4 2003 September 26 2004 September 21 2005 March 4 2006 February 24 2006 June 16 2008 May 16 2008 May 19 2012 April 24 2015 March 11