| Year | Count |
|---|---|
| 1966 | 11 |
| 1967 | 7 |
| 1968 | 40 |
| 1969 | 113 |
| 1970 | 160 |
| 1971 | 108 |
| 1972 | 140 |
| 1973 | 83 |
| 1974 | 74 |
| 1975 | 114 |
| 1976 | 117 |
| 1977 | 126 |
| 1978 | 108 |
| 1979 | 128 |
| 1980 | 83 |
| 1981 | 74 |
| 1982 | 63 |
| 1983 | 72 |
| 1984 | 56 |
| 1985 | 81 |
| 1986 | 75 |
| 1987 | 96 |
| 1988 | 82 |
| 1989 | 93 |
| 1990 | 133 |
| 1991 | 102 |
| 1992 | 122 |
| 1993 | 86 |
| 1994 | 129 |
| 1995 | 62 |
| 1996 | 78 |
| 1997 | 70 |
| 1998 | 65 |
| 1999 | 42 |
| 2000 | 70 |
| 2001 | 60 |
| 2002 | 48 |
| 2003 | 35 |
| 2004 | 46 |
| 2005 | 50 |
| 2006 | 42 |
| 2007 | 39 |
| 2008 | 48 |
| 2009 | 23 |
| 2010 | 10 |
| 2011 | 25 |
| 2013 | 8 |
| 2014 | 22 |
| 2015 | 33 |
| 2016 | 31 |
| 2017 | 15 |
| 2018 | 17 |
| 2019 | 16 |
| 2020 | 35 |
| 2021 | 15 |
| 2022 | 25 |
| 2023 | 18 |
| 2024 | 28 |