| 1968 10 | | | | | | | | | | | | | 1988. 09 1989. 03 | | | 1989.03 1990.10 | | | 1990.10 1991.05 | | | 1991.05 1996.05 | | | 1996.05 1997.01 | | | 1997.01 2001.08 | | | 2001.08 2002.03 | | | 2002.03 2006.06 | | | | 2006.06 2008.10 | | | 2008.10 2011.10 | | | 2011.10 2017.05 | | | 2017.05 2017.10 | | | | 2017.10 2017.12 | | | | | 2017.12 2018.01 | | | | 2018.01 | | | |