| Year | Total | vs prev |
|---|---|---|
| 2012 | 2,125 | +40.9% |
| 2011 | 1,508 | −22.6% |
| 2010 | 1,949 | −0.6% |
| 2009 | 1,961 | −33.3% |
| 2008 | 2,939 | +7.9% |
| 2007 | 2,725 | +12.6% |
| 2006 | 2,420 | +5.2% |
| 2005 | 2,300 | +7.5% |
| 2004 | 2,140 | +24.1% |
| 2003 | 1,725 | +29.1% |
| 2002 | 1,336 | +1.6% |
| 2001 | 1,315 | −22.1% |
| 2000 | 1,687 | +3.5% |
| 1999 | 1,630 | +5.8% |
| 1998 | 1,540 | — |