| Year | Rank | Number |
| 2011 | 12623 | 8 |
| 2010 | 10746 | 10 |
| 2009 | 12901 | 8 |
| 2008 | 7189 | 18 |
| 2007 | 9229 | 13 |
| 2006 | 6453 | 20 |
| 2005 | 7287 | 16 |
| 2004 | 13375 | 7 |
| 2003 | 8205 | 13 |
| 2002 | 6245 | 18 |
| 2001 | 7499 | 14 |
| 2000 | 6062 | 18 |
| 1999 | 6316 | 16 |
| 1998 | 5679 | 18 |
| 1997 | 6007 | 16 |
| 1996 | 5155 | 19 |
| 1995 | 5807 | 16 |
| 1994 | 3832 | 28 |
| 1993 | 7227 | 12 |
| 1992 | 7242 | 12 |
| 1991 | 12174 | 6 |