| Chairman | 2006 – 2008 |
| Board of Directors | 1985 – 1990 |
| Board of Directors | 1985 – 1990 |
| Board of Directors | 1985 – 1990 |
| Board of Directors | 1985 – 1994 |
| Board of Directors | 2011 – 2012 |
| Board of Directors | 2008 – 2018 |
| Board of Directors | 2012 – 2016 |
| Chairman | 2011 – 2012 |
| Board of Directors | 2017 – 2018 |
| Board of Directors | 2016 – 2017 |
| Chairman | 2012 – 2014 |
| Board of Directors | 2001 – 2006 |
| Board of Directors | 1985 – 1998 |
| Chairman | 2017 – 2018 |
| Board of Directors | 1985 – 1990 |
| Board of Directors | 2000 – 2001 |
| Chairman | 2014 – 2017 |
| Board of Directors | 2014 – 2016 |
| Board of Directors | 1985 – 1990 |