| Year | Count |
|---|---|
| 1954 | 6 |
| 1961 | 6 |
| 1967 | 5 |
| 1968 | 6 |
| 1971 | 28 |
| 1972 | 34 |
| 1973 | 33 |
| 1974 | 58 |
| 1975 | 101 |
| 1976 | 73 |
| 1977 | 134 |
| 1978 | 169 |
| 1979 | 133 |
| 1980 | 183 |
| 1981 | 137 |
| 1982 | 111 |
| 1983 | 126 |
| 1984 | 94 |
| 1985 | 169 |
| 1986 | 125 |
| 1987 | 166 |
| 1988 | 168 |
| 1989 | 208 |
| 1990 | 107 |
| 1991 | 122 |
| 1992 | 68 |
| 1993 | 119 |
| 1994 | 164 |
| 1995 | 113 |
| 1996 | 231 |
| 1997 | 252 |
| 1998 | 240 |
| 1999 | 145 |
| 2000 | 155 |
| 2001 | 171 |
| 2002 | 220 |
| 2003 | 239 |
| 2004 | 501 |
| 2005 | 621 |
| 2006 | 491 |
| 2007 | 446 |
| 2008 | 312 |
| 2009 | 239 |
| 2010 | 138 |
| 2011 | 132 |
| 2012 | 79 |
| 2013 | 32 |
| 2015 | 17 |
| 2016 | 30 |
| 2017 | 25 |
| 2018 | 21 |
| 2021 | 5 |
| 2022 | 8 |
| 2023 | 11 |
| 2024 | 11 |