| Current (2) |
| Chairman | 2022 |
| Board of Directors | 2009 |
| Former (19) |
| Board of Directors | 1981 – 1997 |
| Board of Directors | 1981 – 1989 |
| Chairman | 2021 – 2022 |
| Board of Directors | 2002 – 2006 |
| Board of Directors | 1981 – 2009 |
| Board of Directors | 2001 – 2002 |
| Board of Directors | 2012 – 2015 |
| Board of Directors | 2009 – 2009 |
| Board of Directors | 1981 – 1989 |
| Board of Directors | 1981 – 1989 |
| Board of Directors | 1981 – 1992 |
| Board of Directors | 2009 – 2009 |
| Board of Directors | 1998 – 2000 |
| Board of Directors | 1981 – 1988 |
| Board of Directors | 2006 – 2012 |
| Board of Directors | 1981 – 1992 |
| Board of Directors | 1981 – 1992 |
| Chairman | 2015 – 2021 |
| Board of Directors | 2000 – 2001 |