| Year | Total | vs prev |
|---|---|---|
| 2018 | 0 | −100.0% |
| 2017 | 4 | −97.1% |
| 2016 | 137 | −1.4% |
| 2015 | 139 | −18.7% |
| 2014 | 171 | +4.9% |
| 2013 | 163 | −25.6% |
| 2012 | 219 | −8.4% |
| 2011 | 239 | −36.9% |
| 2010 | 379 | −18.0% |
| 2009 | 462 | −36.7% |
| 2008 | 730 | +43.4% |
| 2007 | 509 | −22.1% |
| 2006 | 653 | — |
| 2005 | 653 | +15.0% |
| 2004 | 568 | −16.8% |
| 2003 | 683 | — |