| Year | Rank | Number |
| 2011 | 4900 | 28 |
| 2010 | 6650 | 19 |
| 2009 | 4169 | 36 |
| 2008 | 4751 | 31 |
| 2007 | 4287 | 35 |
| 2006 | 4805 | 29 |
| 2005 | 4367 | 31 |
| 2004 | 7096 | 16 |
| 2003 | 7601 | 14 |
| 2002 | 8873 | 11 |
| 2001 | 6634 | 16 |
| 2000 | 8059 | 12 |
| 1999 | 7745 | 12 |
| 1998 | 6381 | 15 |
| 1997 | 6861 | 13 |
| 1996 | 10631 | 7 |
| 1995 | 8104 | 10 |
| 1994 | 13548 | 5 |
| 1993 | 11838 | 6 |
| 1990 | 10246 | 7 |
| 1989 | 12459 | 5 |
| 1984 | 8173 | 7 |