| Current (2) |
| Board of Directors | 2020 |
| Chairman | 2024 |
| Former (21) |
| Chairman | 1975 – 1989 |
| Chairman | 1975 – 1992 |
| Board of Directors | 2018 – 2020 |
| Board of Directors | 2013 – 2014 |
| Chairman | 2023 – 2024 |
| Chairman | 1975 – 1991 |
| Chairman | 2014 – 2016 |
| Chairman | 1975 – 1988 |
| Deputy Chairman | 1975 – 1997 |
| Deputy Chairman | 1997 – 2001 |
| Board of Directors | 2011 – 2013 |
| Chairman | 1975 – 2003 |
| Chairman | 2007 – 2011 |
| Chairman | 2003 – 2007 |
| Chairman | 2016 – 2023 |
| Deputy Chairman | 1975 – 1989 |
| Board of Directors | 2007 – 2011 |
| Board of Directors | 2020 – 2021 |
| Deputy Chairman | 1975 – 1991 |
| Board of Directors | 2003 – 2005 |
| Board of Directors | 2014 – 2018 |