| Current (1) |
| Chief Executive Officer | 2026 |
| Former (13) |
| Chief Executive Officer | 2007 – 2007 |
| Deputy | 2008 – 2013 |
| Management | 1976 – 1990 |
| Chief Executive Officer | 2014 – 2018 |
| Chief Executive Officer | 2019 – 2025 |
| Chief Executive Officer | 2006 – 2007 |
| Deputy | 1976 – 1996 |
| Chief Executive Officer | 1998 – 1998 |
| Chief Executive Officer | 2026 – 2026 |
| Deputy | 1976 – 1989 |
| Management | 1976 – 1989 |
| Chief Executive Officer | 2025 – 2026 |
| Deputy | 1996 – 1998 |