| Current (4) |
| Board of Directors | 2011 |
| Board of Directors | 2016 |
| Board of Directors | 2023 |
| Chairman | 2017 |
| Former (27) |
| Board of Directors | 1999 – 2008 |
| Chairman | 2004 – 2008 |
| Board of Directors | 1957 – 1996 |
| Board of Directors | 1957 – 1994 |
| Board of Directors | 2019 – 2023 |
| Board of Directors | 1957 – 2003 |
| Board of Directors | 1999 – 2007 |
| Chairman | 2008 – 2017 |
| Board of Directors | 2007 – 2011 |
| Deputy Chairman | 1995 – 2004 |
| Board of Directors | 1997 – 1998 |
| Board of Directors | 2008 – 2008 |
| Board of Directors | 2003 – 2008 |
| Board of Directors | 2015 – 2018 |
| Chairman | 1957 – 1999 |
| Board of Directors | 1957 – 1992 |
| Board of Directors | 1995 – 1999 |
| Chairman | 1957 – 1992 |
| Board of Directors | 2018 – 2019 |
| Board of Directors | 2008 – 2015 |
| Board of Directors | 1995 – 1996 |
| Deputy Chairman | 2008 – 2008 |
| Deputy Chairman | 1999 – 2008 |
| Board of Directors | 2003 – 2007 |
| Board of Directors | 1957 – 1997 |
| Board of Directors | 2007 – 2015 |
| Board of Directors | 1957 – 1991 |