| Issue | Date | Changes |
| 1 | 1984 | Initial Document. |
| 2 | 1986 | Addition of clause 4.1 & 5.1.1 |
| 3 | 2002 | Change of AGM date from June to second meeting in March in clause 4.1 |
| 4 | 2005 | Change of AGM date from second meeting in March to first meeting in May in clause 4.1. Addition of clause 7.1, definition of financial year. |