| Year | Rank | Number |
| 2010 | 11287 | 6 |
| 2003 | 11641 | 5 |
| 2000 | 11111 | 5 |
| 1997 | 8611 | 6 |
| 1993 | 8056 | 6 |
| 1992 | 5838 | 9 |
| 1991 | 4596 | 12 |
| 1990 | 6075 | 8 |
| 1989 | 5863 | 8 |
| 1988 | 3260 | 16 |
| 1987 | 2361 | 24 |
| 1986 | 2180 | 26 |
| 1985 | 1984 | 29 |
| 1984 | 2387 | 21 |
| 1983 | 3981 | 10 |
| 1982 | 4062 | 10 |
| 1981 | 5156 | 7 |
| 1980 | 3158 | 14 |
| 1979 | 3661 | 11 |
| 1978 | 4755 | 7 |
| 1977 | 2715 | 16 |
| 1976 | 3360 | 11 |
| 1975 | 3134 | 12 |