Schedule
| Tax Year | Percentage |
|---|---|
| 1978/79 | 500.7 |
| 1979/80 | 430.2 |
| 1980/81 | 342.9 |
| 1981/82 | 270.9 |
| 1982/83 | 236.9 |
| 1983/84 | 212.8 |
| 1984/85 | 189.7 |
| 1985/86 | 171.7 |
| 1986/87 | 149.5 |
| 1987/88 | 132.3 |
| 1988/89 | 113.7 |
| 1989/90 | 92.9 |
| 1990/91 | 79.8 |
| 1991/92 | 63.3 |
| 1992/93 | 53.3 |
| 1993/94 | 46.0 |
| 1994/95 | 41.6 |
| 1995/96 | 35.7 |
| 1996/97 | 32.0 |
| 1997/98 | 25.7 |
| 1998/99 | 20.1 |
| 1999/2000 | 15.3 |
| 2000/2001 | 8.5 |
| 2001/2002 | 4.3 |