| Year | Total | vs prev |
|---|---|---|
| 2012 | 537 | +27.9% |
| 2011 | 420 | +0.7% |
| 2010 | 417 | +4.0% |
| 2009 | 401 | −15.8% |
| 2008 | 476 | −58.9% |
| 2007 | 1,159 | +35.9% |
| 2006 | 853 | +10.9% |
| 2005 | 769 | −5.8% |
| 2004 | 816 | +12.9% |
| 2003 | 723 | +17.9% |
| 2002 | 613 | +33.6% |
| 2001 | 459 | +4.6% |
| 2000 | 439 | +70.8% |
| 1999 | 257 | +33.9% |
| 1998 | 192 | — |