| Current (6) |
| Chairman | 1983 |
| Board of Directors | 2008 |
| Board of Directors | 2006 |
| Board of Directors | 2013 |
| Board of Directors | 2019 |
| Board of Directors | 2015 |
| Former (18) |
| Board of Directors | 1983 – 1991 |
| Board of Directors | 2000 – 2002 |
| Board of Directors | 2002 – 2008 |
| Board of Directors | 1983 – 1997 |
| Board of Directors | 1983 – 1995 |
| Deputy Chairman | 1983 – 2018 |
| Board of Directors | 1983 – 1991 |
| Board of Directors | 1997 – 2000 |
| Board of Directors | 2004 – 2014 |
| Board of Directors | 1983 – 1991 |
| Board of Directors | 2004 – 2008 |
| Board of Directors | 1999 – 2013 |
| Board of Directors | 1983 – 1991 |
| Board of Directors | 1997 – 2003 |
| Board of Directors | 2002 – 2004 |
| Board of Directors | 1983 – 2000 |
| Board of Directors | 1983 – 1995 |
| Board of Directors | 1983 – 1995 |
