| Year | Count |
|---|---|
| 1978 | 18 |
| 1979 | 6 |
| 1980 | 11 |
| 1981 | 28 |
| 1982 | 7 |
| 1983 | 10 |
| 1984 | 5 |
| 1985 | 22 |
| 1986 | 15 |
| 1987 | 5 |
| 1988 | 15 |
| 1989 | 14 |
| 1990 | 13 |
| 1991 | 8 |
| 1992 | 31 |
| 1993 | 11 |
| 1994 | 16 |
| 1995 | 19 |
| 1996 | 14 |
| 1997 | 6 |
| 1998 | 43 |
| 1999 | 38 |
| 2000 | 36 |
| 2001 | 39 |
| 2002 | 115 |
| 2003 | 87 |
| 2004 | 111 |
| 2005 | 173 |
| 2006 | 152 |
| 2007 | 191 |
| 2008 | 232 |
| 2009 | 131 |
| 2010 | 130 |
| 2011 | 87 |
| 2012 | 103 |
| 2013 | 106 |
| 2014 | 93 |
| 2015 | 99 |
| 2016 | 122 |
| 2017 | 96 |
| 2018 | 98 |
| 2019 | 61 |
| 2020 | 94 |
| 2021 | 119 |
| 2022 | 174 |
| 2023 | 176 |
| 2024 | 165 |