| Current (3) |
| Chairman | 2002 |
| Board of Directors | 2021 |
| Board of Directors | 2021 |
| Former (24) |
| Deputy Chairman | 2007 – 2018 |
| Board of Directors | 2018 – 2019 |
| Deputy Chairman | 2005 – 2005 |
| Board of Directors | 1955 – 1996 |
| Chairman | 2002 – 2002 |
| Board of Directors | 1955 – 2007 |
| Chairman | 1955 – 2002 |
| Chairman | 1955 – 1993 |
| Chairman | 1955 – 1988 |
| Board of Directors | 1955 – 1988 |
| Board of Directors | 1955 – 1995 |
| Chairman | 1995 – 1997 |
| Board of Directors | 2019 – 2020 |
| Deputy Chairman | 1955 – 1994 |
| Board of Directors | 2011 – 2018 |
| Board of Directors | 2002 – 2005 |
| Board of Directors | 1955 – 1990 |
| Board of Directors | 2019 – 2021 |
| Deputy Chairman | 1955 – 1996 |
| Board of Directors | 1955 – 2003 |
| Deputy Chairman | 2005 – 2007 |
| Chairman | 1955 – 1995 |
| Board of Directors | 2003 – 2007 |
| Board of Directors | 1955 – 1991 |