| Former (17) |
| Management | 1952 – 1989 |
| Unofficial title | 1952 – 1990 |
| Unofficial title | 1952 – 1998 |
| Unofficial title | 1952 – 1998 |
| Unofficial title | 1952 – 2001 |
| Audit | 1952 – 1992 |
| Unofficial title | 2002 – 2005 |
| Management | 1952 – 2005 |
| Unofficial title | 1952 – 1990 |
| Unofficial title | 1998 – 2001 |
| Management | 1952 – 1991 |
| Chief Executive Officer | 1952 – 2005 |
| Unofficial title | 2002 – 2005 |
| Unofficial title | 1952 – 1994 |
| Unofficial title | 1952 – 1990 |
| Management | 1952 – 2005 |
| Management | 1952 – 1992 |