| 1968 8 | 1990 7 1996 10 | | 1990.7 1994.8 | | | 1994.8 2007.8 | | 1996 12 | 2000 12 | 2002 8 | | 2007.8 2011.5 | | 2011.5 2013.6 | | 2013.6 2015.12 | | 2015.12 2017.12 | | | 2017.12 2019.9 | | | | 2019.9 | | | | |