| Year | Count |
|---|---|
| 1965 | 6 |
| 1967 | 5 |
| 1970 | 8 |
| 1971 | 6 |
| 1972 | 6 |
| 1973 | 6 |
| 1975 | 17 |
| 1976 | 5 |
| 1977 | 7 |
| 1978 | 11 |
| 1979 | 35 |
| 1980 | 8 |
| 1981 | 13 |
| 1982 | 17 |
| 1983 | 21 |
| 1984 | 6 |
| 1985 | 13 |
| 1986 | 27 |
| 1987 | 15 |
| 1988 | 34 |
| 1989 | 39 |
| 1990 | 58 |
| 1991 | 64 |
| 1992 | 109 |
| 1993 | 99 |
| 1994 | 73 |
| 1995 | 94 |
| 1996 | 101 |
| 1997 | 114 |
| 1998 | 123 |
| 1999 | 161 |
| 2000 | 174 |
| 2001 | 196 |
| 2002 | 112 |
| 2003 | 140 |
| 2004 | 252 |
| 2005 | 277 |
| 2006 | 325 |
| 2007 | 251 |
| 2008 | 255 |
| 2009 | 201 |
| 2010 | 210 |
| 2011 | 144 |
| 2012 | 252 |
| 2013 | 237 |
| 2014 | 200 |
| 2015 | 215 |
| 2016 | 263 |
| 2017 | 157 |
| 2018 | 205 |
| 2019 | 226 |
| 2020 | 164 |
| 2021 | 251 |
| 2022 | 227 |
| 2023 | 235 |
| 2024 | 258 |