| Year | Count |
|---|---|
| 1956 | 12 |
| 1957 | 10 |
| 1972 | 10 |
| 1973 | 10 |
| 1975 | 5 |
| 1976 | 12 |
| 1977 | 5 |
| 1978 | 5 |
| 1980 | 6 |
| 1981 | 10 |
| 1990 | 10 |
| 1991 | 7 |
| 1993 | 5 |
| 1995 | 5 |
| 1998 | 7 |
| 1999 | 22 |
| 2000 | 30 |
| 2001 | 31 |
| 2004 | 22 |
| 2005 | 38 |
| 2006 | 31 |
| 2007 | 32 |
| 2008 | 77 |
| 2009 | 28 |
| 2010 | 70 |
| 2011 | 61 |
| 2012 | 62 |
| 2013 | 33 |
| 2014 | 32 |
| 2015 | 21 |
| 2016 | 21 |
| 2017 | 12 |
| 2018 | 8 |
| 2019 | 25 |
| 2020 | 6 |
| 2021 | 10 |
| 2022 | 12 |
| 2023 | 19 |
| 2024 | 17 |