| Year | Count |
|---|---|
| 1970 | 6 |
| 1994 | 6 |
| 1995 | 6 |
| 1996 | 5 |
| 1997 | 9 |
| 1998 | 12 |
| 1999 | 7 |
| 2000 | 11 |
| 2001 | 17 |
| 2002 | 16 |
| 2003 | 22 |
| 2004 | 22 |
| 2005 | 33 |
| 2006 | 35 |
| 2007 | 57 |
| 2008 | 49 |
| 2009 | 59 |
| 2010 | 68 |
| 2011 | 65 |
| 2012 | 86 |
| 2013 | 103 |
| 2014 | 126 |
| 2015 | 143 |
| 2016 | 555 |
| 2017 | 915 |
| 2018 | 1,221 |
| 2019 | 906 |
| 2020 | 934 |
| 2021 | 994 |
| 2022 | 1,106 |
| 2023 | 962 |
| 2024 | 832 |