| Year | Rank | Number |
| 2011 | 11291 | 9 |
| 2010 | 13716 | 7 |
| 2009 | 7691 | 16 |
| 2008 | 10189 | 11 |
| 2007 | 8592 | 14 |
| 2006 | 5741 | 23 |
| 2005 | 6875 | 17 |
| 2004 | 5790 | 21 |
| 2003 | 4560 | 28 |
| 2002 | 5476 | 21 |
| 2001 | 7813 | 13 |
| 2000 | 4201 | 29 |
| 1999 | 3322 | 38 |
| 1998 | 4258 | 26 |
| 1997 | 6553 | 14 |
| 1996 | 3306 | 35 |
| 1995 | 13802 | 5 |
| 1994 | 13812 | 5 |
| 1991 | 11750 | 6 |
| 1987 | 11574 | 5 |
| 1986 | 11170 | 5 |