| Year | Total | vs prev |
|---|---|---|
| 2012 | 2,359 | +18.1% |
| 2011 | 1,997 | −16.2% |
| 2010 | 2,382 | −7.4% |
| 2009 | 2,572 | −16.7% |
| 2008 | 3,087 | +22.9% |
| 2007 | 2,511 | +33.6% |
| 2006 | 1,880 | −10.3% |
| 2005 | 2,096 | +21.7% |
| 2004 | 1,722 | +18.5% |
| 2003 | 1,453 | +5.4% |
| 2002 | 1,378 | −19.0% |
| 2001 | 1,702 | −5.5% |
| 2000 | 1,802 | +1.0% |
| 1999 | 1,784 | +11.1% |
| 1998 | 1,606 | — |