| Chairman | 1997 – 2005 |
| Board of Directors | 1974 – 1988 |
| Chairman | 1974 – 1987 |
| Board of Directors | 1997 – 1999 |
| Board of Directors | 2000 – 2005 |
| Board of Directors | 2014 – 2014 |
| Board of Directors | 1974 – 1989 |
| Chairman | 2011 – 2014 |
| Board of Directors | 2005 – 2014 |
| Board of Directors | 1974 – 2000 |
| Board of Directors | 1999 – 2006 |
| Board of Directors | 2011 – 2014 |
| Chairman | 1974 – 1989 |
| Board of Directors | 1974 – 1987 |
| Chairman | 1974 – 1988 |
| Chairman | 2005 – 2009 |
| Chairman | 2009 – 2011 |
| Deputy Chairman | 1974 – 1988 |
| Board of Directors | 1974 – 1987 |
| Board of Directors | 1974 – 2000 |
| Deputy Chairman | 1974 – 1989 |