Term of office
31 October 2017 - 30 January 2023
10 November 2014 - 30 October 2017
31 October 2011 - 10 November 2014
31 October 2007 - 31 October 2011
31 October 2003 - 31 October 2007
28 November 2000 - 31 October 2003
17 February 1997 - 28 November 2000
01 March 1993 - 17 February 1997
01 July 1989 - 01 March 1993
01 January 1981 - 01 July 1989
01 June 1978 - 01 January 1981
10 December 1973 - 12 November 1975
04 March 1970 - 10 December 1973
01 October 1964 - 03 March 1970
01 April 1961 - 01 October 1964
01 July 1956 - 01 April 1961
01 July 1951 - 01 July 1956
01 July 1946 - 01 July 1951
29 March 1937 - 01 July 1946
12 June 1931 - 29 March 1937
01 March 1927 - 12 June 1931
11 December 1929 - 12 June 1931
15 December 1926 - 11 December 1929
17 January 1921 - 16 January 1926
01 August 1919 - 17 January 1921
25 March 1912 - 01 August 1919
