From Wikipedia, the free encyclopedia
29 December 1980–2 January 1983
[edit]3 January 1983–July 1987
[edit]July 1987–April 1989
[edit]April 1989–April 1991
[edit]September 1989–February 1993
[edit]April 1991–September 1996
[edit]September 1996–24 May 1998
[edit]25 May 1998–7 September 2003
[edit]8 September 2003–10 March 2006
[edit]11 March 2006–31 October 2009
[edit]1 November 2009–13 January 2013
[edit]14 January 2013–present
[edit] 
