| Year | Count |
|---|---|
| 1963 | 5 |
| 1964 | 5 |
| 1966 | 5 |
| 1967 | 7 |
| 1969 | 5 |
| 1970 | 6 |
| 1971 | 8 |
| 1972 | 6 |
| 1973 | 8 |
| 1974 | 10 |
| 1975 | 6 |
| 1977 | 5 |
| 1978 | 23 |
| 1979 | 5 |
| 1980 | 30 |
| 1981 | 5 |
| 1982 | 14 |
| 1983 | 5 |
| 1984 | 6 |
| 1985 | 61 |
| 1987 | 14 |
| 1988 | 29 |
| 1989 | 48 |
| 1990 | 60 |
| 1991 | 66 |
| 1992 | 112 |
| 1993 | 51 |
| 1994 | 61 |
| 1995 | 98 |
| 1996 | 107 |
| 1997 | 90 |
| 1998 | 172 |
| 1999 | 260 |
| 2000 | 221 |
| 2001 | 290 |
| 2002 | 250 |
| 2003 | 183 |
| 2004 | 206 |
| 2005 | 295 |
| 2006 | 328 |
| 2007 | 284 |
| 2008 | 299 |
| 2009 | 293 |
| 2010 | 338 |
| 2011 | 188 |
| 2012 | 268 |
| 2013 | 217 |
| 2014 | 234 |
| 2015 | 198 |
| 2016 | 202 |
| 2017 | 141 |
| 2018 | 163 |
| 2019 | 161 |
| 2020 | 107 |
| 2021 | 139 |
| 2022 | 93 |
| 2023 | 121 |
| 2024 | 154 |