| Year | Rank | Number |
| 1998 | 16164 | 5 |
| 1997 | 11872 | 7 |
| 1996 | 7503 | 12 |
| 1995 | 7433 | 12 |
| 1994 | 3684 | 30 |
| 1993 | 3565 | 31 |
| 1992 | 3262 | 35 |
| 1991 | 3192 | 35 |
| 1990 | 2792 | 42 |
| 1989 | 2855 | 39 |
| 1988 | 3025 | 34 |
| 1987 | 3719 | 24 |
| 1986 | 4159 | 20 |
| 1985 | 3490 | 25 |
| 1984 | 4293 | 18 |
| 1983 | 3776 | 21 |
| 1982 | 5834 | 12 |
| 1981 | 5191 | 14 |
| 1980 | 6674 | 10 |
| 1979 | 6090 | 11 |
| 1978 | 6813 | 9 |
| 1977 | 9395 | 6 |
| 1974 | 9923 | 5 |