| Year | Rank | Number |
| 2011 | 14514 | 7 |
| 2010 | 9667 | 12 |
| 2009 | 8740 | 14 |
| 2008 | 8867 | 14 |
| 2007 | 9430 | 13 |
| 2006 | 7418 | 17 |
| 2005 | 5746 | 22 |
| 2004 | 7765 | 15 |
| 2003 | 7148 | 16 |
| 2002 | 5052 | 24 |
| 2001 | 4011 | 32 |
| 2000 | 3792 | 34 |
| 1999 | 3708 | 33 |
| 1998 | 3411 | 36 |
| 1997 | 2867 | 43 |
| 1996 | 2889 | 42 |
| 1995 | 2832 | 43 |
| 1994 | 2291 | 58 |
| 1993 | 2238 | 59 |
| 1992 | 1869 | 76 |
| 1991 | 2130 | 63 |
| 1990 | 1665 | 89 |
| 1989 | 1539 | 93 |
| 1988 | 1415 | 99 |
| 1987 | 1376 | 99 |
| 1986 | 834 | 200 |
| 1985 | 1123 | 129 |