| Chairman | 2012 – 2013 |
| Board of Directors | 1976 – 1990 |
| Board of Directors | 1976 – 2001 |
| Board of Directors | 2001 – 2013 |
| Board of Directors | 2004 – 2009 |
| Board of Directors | 1976 – 2004 |
| Board of Directors | 1976 – 1990 |
| Board of Directors | 1976 – 1997 |
| Board of Directors | 1976 – 2001 |
| Board of Directors | 1976 – 2001 |
| Board of Directors | 2009 – 2013 |
| Board of Directors | 1976 – 1989 |
| Board of Directors | 1976 – 2001 |