| Current (2) |
| Chairman | 2020 |
| Board of Directors | 2009 |
| Former (28) |
| Board of Directors | 2018 – 2021 |
| Board of Directors | 2009 – 2009 |
| Board of Directors | 2008 – 2009 |
| Board of Directors | 2008 – 2009 |
| Board of Directors | 2018 – 2021 |
| Board of Directors | 2007 – 2008 |
| Board of Directors | 2012 – 2015 |
| Chairman | 2000 – 2009 |
| Board of Directors | 2017 – 2020 |
| Board of Directors | 2000 – 2008 |
| Board of Directors | 1980 – 1999 |
| Board of Directors | 1999 – 2000 |
| Board of Directors | 2000 – 2003 |
| Board of Directors | 1980 – 1998 |
| Board of Directors | 2009 – 2010 |
| Board of Directors | 2001 – 2013 |
| Chairman | 2009 – 2020 |
| Board of Directors | 2000 – 2008 |
| Board of Directors | 2013 – 2018 |
| Board of Directors | 1980 – 2001 |
| Board of Directors | 1998 – 1998 |
| Board of Directors | 1980 – 1994 |
| Board of Directors | 1999 – 2000 |
| Board of Directors | 2001 – 2006 |
| Board of Directors | 1980 – 1993 |
| Chairman | 1998 – 2000 |
| Board of Directors | 2001 – 2001 |
| Board of Directors | 2006 – 2018 |