| Year | Total | vs prev |
|---|---|---|
| 2020 | 0 | −100.0% |
| 2019 | 112 | −56.8% |
| 2018 | 259 | −2.6% |
| 2017 | 266 | −15.6% |
| 2016 | 315 | +5.7% |
| 2015 | 298 | +6.4% |
| 2014 | 280 | +57.3% |
| 2013 | 178 | −14.8% |
| 2012 | 209 | +8.3% |
| 2011 | 193 | −43.7% |
| 2010 | 343 | +16.3% |
| 2009 | 295 | −11.9% |
| 2008 | 335 | −45.7% |
| 2007 | 617 | +22.4% |
| 2006 | 504 | +5.7% |
| 2005 | 477 | −4.8% |
| 2004 | 501 | +69.3% |
| 2003 | 296 | −29.4% |
| 2002 | 419 | +21.1% |
| 2001 | 346 | +44.8% |
| 2000 | 239 | +127.6% |
| 1999 | 105 | +10400.0% |
| 1998 | 1 | — |