| Former (18) |
| Board of Directors | 1988 – 1993 |
| Chairman | 1993 – 1993 |
| Chairman | 2005 – 2012 |
| Board of Directors | 1988 – 1995 |
| Chairman | 1998 – 2005 |
| Board of Directors | 1988 – 1996 |
| Board of Directors | 1988 – 1988 |
| Board of Directors | 2014 – 2018 |
| Board of Directors | 2012 – 2014 |
| Chairman | 2014 – 2015 |
| Chairman | 1995 – 1998 |
| Board of Directors | 1988 – 1995 |
| Board of Directors | 1995 – 2012 |
| Chairman | 1988 – 1993 |
| Board of Directors | 2012 – 2014 |
| Chairman | 1988 – 1988 |
| Chairman | 1993 – 1995 |
| Chairman | 2015 – 2018 |