| Year | Count |
|---|---|
| 1973 | 7 |
| 1977 | 14 |
| 1979 | 14 |
| 1981 | 5 |
| 1982 | 6 |
| 1985 | 11 |
| 1986 | 10 |
| 1987 | 16 |
| 1989 | 5 |
| 1991 | 5 |
| 1992 | 5 |
| 1993 | 14 |
| 1994 | 12 |
| 1996 | 13 |
| 1997 | 7 |
| 1998 | 29 |
| 1999 | 10 |
| 2000 | 40 |
| 2001 | 137 |
| 2002 | 131 |
| 2003 | 121 |
| 2004 | 124 |
| 2005 | 124 |
| 2006 | 92 |
| 2007 | 109 |
| 2008 | 116 |
| 2009 | 117 |
| 2010 | 95 |
| 2011 | 135 |
| 2012 | 86 |
| 2013 | 82 |
| 2014 | 66 |
| 2015 | 95 |
| 2016 | 73 |
| 2017 | 90 |
| 2018 | 94 |
| 2019 | 101 |
| 2020 | 108 |
| 2021 | 104 |
| 2022 | 122 |
| 2023 | 162 |
| 2024 | 165 |