| Year | Count |
|---|---|
| 1962 | 5 |
| 1963 | 5 |
| 1966 | 7 |
| 1967 | 12 |
| 1968 | 8 |
| 1969 | 5 |
| 1970 | 7 |
| 1972 | 8 |
| 1973 | 5 |
| 1974 | 7 |
| 1976 | 14 |
| 1977 | 14 |
| 1978 | 27 |
| 1979 | 16 |
| 1980 | 5 |
| 1981 | 8 |
| 1982 | 8 |
| 1983 | 11 |
| 1984 | 8 |
| 1985 | 38 |
| 1986 | 27 |
| 1987 | 72 |
| 1988 | 80 |
| 1989 | 91 |
| 1990 | 79 |
| 1991 | 125 |
| 1992 | 129 |
| 1993 | 121 |
| 1994 | 137 |
| 1995 | 90 |
| 1996 | 163 |
| 1997 | 217 |
| 1998 | 202 |
| 1999 | 134 |
| 2000 | 156 |
| 2001 | 182 |
| 2002 | 123 |
| 2003 | 188 |
| 2004 | 257 |
| 2005 | 238 |
| 2006 | 208 |
| 2007 | 185 |
| 2008 | 194 |
| 2009 | 116 |
| 2010 | 84 |
| 2011 | 95 |
| 2012 | 105 |
| 2013 | 24 |
| 2014 | 72 |
| 2015 | 60 |
| 2016 | 85 |
| 2017 | 67 |
| 2018 | 20 |
| 2019 | 36 |
| 2020 | 59 |
| 2021 | 5 |
| 2022 | 28 |
| 2023 | 15 |
| 2024 | 17 |