| Year | Rank | Number |
| 2008 | 19333 | 5 |
| 2007 | 14855 | 7 |
| 2004 | 13647 | 7 |
| 2003 | 11978 | 8 |
| 2001 | 12917 | 7 |
| 2000 | 10413 | 9 |
| 1999 | 8577 | 11 |
| 1998 | 11919 | 7 |
| 1997 | 10418 | 8 |
| 1996 | 10155 | 8 |
| 1995 | 11274 | 7 |
| 1993 | 12808 | 6 |
| 1991 | 12483 | 6 |
| 1990 | 12307 | 6 |
| 1989 | 10403 | 7 |
| 1987 | 10692 | 6 |
| 1985 | 8006 | 8 |
| 1983 | 11278 | 5 |
| 1981 | 11407 | 5 |