| Year | Total | vs prev |
|---|---|---|
| 2022 | 0 | −100.0% |
| 2021 | 1 | −95.8% |
| 2020 | 24 | −22.6% |
| 2019 | 31 | −62.7% |
| 2018 | 83 | −47.5% |
| 2017 | 158 | −20.2% |
| 2016 | 198 | +42.4% |
| 2015 | 139 | −45.5% |
| 2014 | 255 | −48.4% |
| 2013 | 494 | −20.8% |
| 2012 | 624 | +447.4% |
| 2011 | 114 | −39.7% |
| 2010 | 189 | −11.7% |
| 2009 | 214 | −48.9% |
| 2008 | 419 | −17.5% |
| 2007 | 508 | −21.6% |
| 2006 | 648 | −12.1% |
| 2005 | 737 | — |