| Year | Rank | Number |
| 2010 | 15734 | 6 |
| 2007 | 18751 | 5 |
| 2006 | 15920 | 6 |
| 1998 | 15127 | 5 |
| 1995 | 12397 | 6 |
| 1994 | 9935 | 8 |
| 1993 | 12417 | 6 |
| 1992 | 12373 | 6 |
| 1991 | 6055 | 15 |
| 1990 | 5954 | 15 |
| 1989 | 6693 | 12 |
| 1988 | 5129 | 16 |
| 1987 | 5150 | 15 |
| 1986 | 5904 | 12 |
| 1985 | 5163 | 14 |
| 1984 | 6038 | 11 |
| 1983 | 4972 | 14 |
| 1982 | 4406 | 17 |
| 1981 | 5375 | 13 |
| 1980 | 5652 | 12 |
| 1978 | 7204 | 8 |
| 1977 | 8874 | 6 |
| 1976 | 7598 | 7 |