| Year | Count |
|---|---|
| 1975 | 7 |
| 1976 | 9 |
| 1977 | 15 |
| 1978 | 10 |
| 1978 | 12 |
| 1979 | 17 |
| 1980 | 37 |
| 1981 | 29 |
| 1982 | 17 |
| 1983 | 29 |
| 1984 | 17 |
| 1985 | 10 |
| 1985 | 57 |
| 1986 | 36 |
| 1987 | 37 |
| 1988 | 15 |
| 1989 | 27 |
| 1990 | 58 |
| 1991 | 90 |
| 1992 | 95 |
| 1993 | 85 |
| 1994 | 59 |
| 1995 | 39 |
| 1996 | 51 |
| 1997 | 61 |
| 1998 | 67 |
| 1999 | 75 |
| 2000 | 103 |
| 2001 | 147 |
| 2002 | 101 |
| 2003 | 104 |
| 2004 | 111 |
| 2005 | 121 |
| 2006 | 135 |
| 2007 | 133 |
| 2008 | 165 |
| 2009 | 86 |
| 2010 | 110 |
| 2011 | 106 |
| 2012 | 72 |
| 2013 | 51 |
| 2014 | 68 |
| 2015 | 33 |
| 2016 | 26 |
| 2017 | 55 |
| 2018 | 108 |
| 2019 | 184 |
| 2020 | 169 |
| 2021 | 132 |
| 2022 | 145 |
| 2023 | 125 |
| 2024 | 85 |