| Current (8) |
| Management | 2017 |
| Stakeholder | 2021 |
| Management | 2020 |
| Management | 2019 |
| Management | 2017 |
| Management | 2017 |
| Management | 2019 |
| Management | 2017 |
| Former (13) |
| Management | 2017 – 2018 |
| Management | 2017 – 2020 |
| Stakeholder | 1972 – 2011 |
| Stakeholder | 1972 – 2001 |
| Stakeholder | 1997 – 2011 |
| Stakeholder | 2009 – 2011 |
| Management | 2017 – 2019 |
| Stakeholder | 1972 – 2009 |
| Stakeholder | 1987 – 2007 |
| Stakeholder | 1972 – 1999 |
| Stakeholder | 1990 – 1999 |
| Stakeholder | 1998 – 2013 |
| Stakeholder | 1983 – 2011 |