| Year | Rank | Number |
| 2011 | 2953 | 39 |
| 2010 | 3394 | 32 |
| 2009 | 3159 | 36 |
| 2008 | 2893 | 41 |
| 2007 | 3042 | 38 |
| 2006 | 2483 | 49 |
| 2005 | 4245 | 21 |
| 2004 | 3916 | 23 |
| 2003 | 5672 | 13 |
| 2002 | 4374 | 18 |
| 2001 | 3765 | 22 |
| 2000 | 4660 | 16 |
| 1999 | 4616 | 15 |
| 1998 | 6506 | 9 |
| 1997 | 7597 | 7 |
| 1996 | 4480 | 14 |
| 1995 | 9410 | 5 |
| 1994 | 6616 | 8 |
| 1992 | 5830 | 9 |
| 1991 | 6824 | 7 |
| 1990 | 7515 | 6 |