| Year | Count |
|---|---|
| 1971 | 15 |
| 1973 | 5 |
| 1975 | 7 |
| 1976 | 5 |
| 1977 | 5 |
| 1978 | 9 |
| 1981 | 5 |
| 1991 | 6 |
| 1992 | 5 |
| 1994 | 5 |
| 1997 | 37 |
| 1998 | 36 |
| 1999 | 6 |
| 2000 | 6 |
| 2001 | 18 |
| 2002 | 103 |
| 2003 | 6 |
| 2004 | 12 |
| 2005 | 19 |
| 2006 | 39 |
| 2007 | 8 |
| 2008 | 18 |
| 2009 | 28 |
| 2010 | 36 |
| 2011 | 10 |
| 2012 | 18 |
| 2013 | 14 |
| 2014 | 22 |
| 2015 | 20 |
| 2018 | 9 |
| 2019 | 12 |
| 2020 | 20 |
| 2021 | 33 |
| 2022 | 22 |
| 2023 | 40 |
| 2024 | 30 |