| Year | Count |
|---|---|
| 1965 | 14 |
| 1968 | 5 |
| 1969 | 50 |
| 1970 | 65 |
| 1971 | 169 |
| 1972 | 101 |
| 1973 | 148 |
| 1974 | 124 |
| 1975 | 187 |
| 1976 | 159 |
| 1977 | 227 |
| 1978 | 133 |
| 1979 | 143 |
| 1980 | 131 |
| 1981 | 92 |
| 1982 | 74 |
| 1983 | 38 |
| 1984 | 80 |
| 1985 | 79 |
| 1986 | 57 |
| 1987 | 59 |
| 1988 | 113 |
| 1989 | 131 |
| 1990 | 148 |
| 1991 | 166 |
| 1992 | 144 |
| 1993 | 117 |
| 1994 | 92 |
| 1995 | 134 |
| 1996 | 113 |
| 1997 | 87 |
| 1998 | 109 |
| 1999 | 49 |
| 2000 | 93 |
| 2001 | 127 |
| 2002 | 46 |
| 2003 | 40 |
| 2004 | 30 |
| 2005 | 80 |
| 2006 | 53 |
| 2007 | 17 |
| 2008 | 85 |
| 2009 | 34 |
| 2010 | 8 |
| 2011 | 22 |
| 2012 | 41 |
| 2013 | 17 |
| 2014 | 12 |
| 2015 | 20 |
| 2016 | 30 |
| 2017 | 8 |
| 2018 | 6 |
| 2019 | 6 |
| 2021 | 10 |
| 2023 | 5 |