| Year | Total | vs prev |
|---|---|---|
| 2007 | 0 | −100.0% |
| 2006 | 3 | −91.9% |
| 2005 | 37 | −56.0% |
| 2004 | 84 | −47.8% |
| 2003 | 161 | −34.0% |
| 2002 | 244 | −46.8% |
| 2001 | 459 | +102.2% |
| 2000 | 227 | +609.4% |
| 1999 | 32 | −37.3% |
| 1998 | 51 | −43.3% |
| 1997 | 90 | −8.2% |
| 1996 | 98 | −3.9% |
| 1995 | 102 | −35.0% |
| 1994 | 157 | +41.4% |
| 1993 | 111 | −40.6% |
| 1992 | 187 | −31.5% |
| 1991 | 273 | — |