| Year | Rank | Number |
| 2011 | 13441 | 7 |
| 2010 | 12375 | 8 |
| 2009 | 9967 | 11 |
| 2008 | 13966 | 7 |
| 2007 | 14073 | 7 |
| 2006 | 15346 | 6 |
| 2005 | 10208 | 10 |
| 2004 | 14385 | 6 |
| 2003 | 16048 | 5 |
| 2002 | 11252 | 8 |
| 2001 | 8249 | 12 |
| 2000 | 11931 | 7 |
| 1999 | 11522 | 7 |
| 1998 | 9335 | 9 |
| 1997 | 9893 | 8 |
| 1996 | 9667 | 8 |
| 1995 | 9654 | 8 |
| 1994 | 11920 | 6 |
| 1992 | 13480 | 5 |
| 1987 | 9930 | 6 |
| 1981 | 8182 | 7 |
| 1980 | 10504 | 5 |