| Year | Count |
|---|---|
| 1935 | 5 |
| 1936 | 5 |
| 1938 | 6 |
| 1941 | 15 |
| 1961 | 18 |
| 1963 | 5 |
| 1967 | 15 |
| 1968 | 5 |
| 1970 | 7 |
| 1973 | 8 |
| 1974 | 11 |
| 1975 | 23 |
| 1976 | 13 |
| 1977 | 7 |
| 1978 | 26 |
| 1979 | 35 |
| 1980 | 25 |
| 1981 | 14 |
| 1982 | 41 |
| 1983 | 26 |
| 1984 | 15 |
| 1985 | 20 |
| 1986 | 26 |
| 1987 | 34 |
| 1988 | 15 |
| 1989 | 12 |
| 1990 | 27 |
| 1991 | 28 |
| 1992 | 54 |
| 1993 | 30 |
| 1994 | 21 |
| 1995 | 29 |
| 1996 | 104 |
| 1997 | 52 |
| 1998 | 82 |
| 1999 | 35 |
| 2000 | 108 |
| 2001 | 110 |
| 2002 | 77 |
| 2003 | 116 |
| 2004 | 199 |
| 2005 | 222 |
| 2006 | 161 |
| 2007 | 203 |
| 2008 | 163 |
| 2009 | 74 |
| 2010 | 41 |
| 2011 | 51 |
| 2012 | 43 |
| 2015 | 25 |
| 2016 | 30 |
| 2017 | 17 |
| 2018 | 9 |
| 2019 | 15 |
| 2020 | 21 |
| 2021 | 15 |
| 2022 | 14 |
| 2023 | 12 |
| 2024 | 8 |