| Current (2) |
| Chairman | 2021 |
| Board of Directors | 2002 |
| Former (18) |
| Board of Directors | 2018 – 2022 |
| Board of Directors | 2002 – 2010 |
| Board of Directors | 1988 – 1993 |
| Chairman | 2014 – 2021 |
| Chairman | 1998 – 2000 |
| Board of Directors | 2010 – 2014 |
| Board of Directors | 2016 – 2018 |
| Chairman | 2012 – 2014 |
| Board of Directors | 1999 – 2002 |
| Board of Directors | 1997 – 2002 |
| Board of Directors | 2014 – 2016 |
| Board of Directors | 1996 – 1998 |
| Board of Directors | 1997 – 1997 |
| Board of Directors | 1988 – 1997 |
| Board of Directors | 1988 – 1996 |
| Board of Directors | 2012 – 2012 |
| Board of Directors | 1988 – 1990 |
| Board of Directors | 1988 – 1999 |