| Year | Count |
|---|---|
| 1971 | 7 |
| 1972 | 5 |
| 1973 | 8 |
| 1974 | 9 |
| 1975 | 5 |
| 1976 | 6 |
| 1977 | 5 |
| 1980 | 6 |
| 1981 | 6 |
| 1990 | 5 |
| 1991 | 5 |
| 1994 | 7 |
| 1996 | 6 |
| 1998 | 12 |
| 1999 | 8 |
| 2000 | 9 |
| 2001 | 42 |
| 2002 | 45 |
| 2003 | 51 |
| 2004 | 63 |
| 2005 | 75 |
| 2006 | 110 |
| 2007 | 100 |
| 2008 | 94 |
| 2009 | 97 |
| 2010 | 108 |
| 2011 | 79 |
| 2012 | 99 |
| 2013 | 73 |
| 2014 | 85 |
| 2015 | 110 |
| 2016 | 104 |
| 2017 | 139 |
| 2018 | 109 |
| 2019 | 104 |
| 2020 | 92 |
| 2021 | 230 |
| 2022 | 194 |
| 2023 | 277 |
| 2024 | 268 |