| Year | Count |
|---|---|
| 1970 | 21 |
| 1971 | 32 |
| 1972 | 19 |
| 1973 | 5 |
| 1974 | 5 |
| 1975 | 5 |
| 1983 | 10 |
| 1996 | 6 |
| 1997 | 11 |
| 1999 | 23 |
| 2000 | 36 |
| 2001 | 41 |
| 2002 | 73 |
| 2003 | 34 |
| 2004 | 112 |
| 2005 | 65 |
| 2006 | 53 |
| 2007 | 92 |
| 2008 | 74 |
| 2009 | 42 |
| 2010 | 86 |
| 2011 | 69 |
| 2012 | 38 |
| 2013 | 20 |
| 2014 | 54 |
| 2015 | 54 |
| 2016 | 44 |
| 2017 | 27 |
| 2018 | 14 |
| 2019 | 28 |
| 2020 | 27 |
| 2021 | 28 |
| 2022 | 30 |
| 2023 | 25 |
| 2024 | 27 |