| Chairman | 2016 – 2018 |
| Board of Directors | 1986 – 1991 |
| Board of Directors | 2008 – 2009 |
| Chairman | 2015 – 2016 |
| Board of Directors | 2018 – 2018 |
| Board of Directors | 2009 – 2011 |
| Board of Directors | 1986 – 2007 |
| Board of Directors | 1986 – 1992 |
| Board of Directors | 1992 – 1997 |
| Board of Directors | 2001 – 2008 |
| Board of Directors | 2016 – 2017 |
| Board of Directors | 1997 – 2011 |
| Board of Directors | 2008 – 2018 |
| Chairman | 2018 – 2018 |
| Board of Directors | 2016 – 2018 |
| Board of Directors | 2002 – 2002 |
| Board of Directors | 2008 – 2018 |
| Board of Directors | 2018 – 2018 |
| Board of Directors | 2011 – 2015 |
| Board of Directors | 2016 – 2018 |
| Board of Directors | 1986 – 1997 |