| Year | Rank | Number |
| 2011 | 3390 | 47 |
| 2010 | 3118 | 53 |
| 2009 | 4553 | 32 |
| 2008 | 5145 | 28 |
| 2007 | 4700 | 31 |
| 2006 | 4471 | 32 |
| 2005 | 5122 | 25 |
| 2004 | 4953 | 26 |
| 2003 | 5850 | 20 |
| 2002 | 4655 | 26 |
| 2001 | 5400 | 21 |
| 2000 | 6537 | 16 |
| 1999 | 5955 | 17 |
| 1998 | 8692 | 10 |
| 1997 | 11063 | 7 |
| 1996 | 5829 | 16 |
| 1995 | 7602 | 11 |
| 1994 | 6375 | 14 |
| 1993 | 7586 | 11 |
| 1992 | 6361 | 14 |
| 1991 | 7037 | 12 |
| 1989 | 8889 | 8 |
| 1988 | 8514 | 8 |
| 1987 | 10029 | 6 |
| 1986 | 9745 | 6 |