| 1970 3 1990 7 1994 | 7 | | | | 1986 9 1990 7 | | | 1990 7 1995 3 | | | 1995 3 1997 6 | | 1996 10 2002 6 | | | 1997 6 2002 6 | | | 2002 6 2004 7 | | 2004 7 2005 10 | | | 2005 10 2008 10 | | 2006 4 | | 2008 10 2012 4 | | 2012 4 2012 12 | | | 2012 8 2015 1 | | | 2012 12 2015 11 | | | 2015 11 2016 7 | | 2016 7 2019 1 | | | 2019 1 2019 4 | | | 2019 4 2021 7 | | 2021 7 — | |