| Year | Count |
|---|---|
| 1967 | 6 |
| 1969 | 6 |
| 1970 | 5 |
| 1971 | 8 |
| 1973 | 5 |
| 1974 | 6 |
| 1976 | 8 |
| 1977 | 18 |
| 1978 | 10 |
| 1979 | 17 |
| 1982 | 8 |
| 1983 | 5 |
| 1984 | 8 |
| 1985 | 16 |
| 1986 | 5 |
| 1987 | 24 |
| 1988 | 10 |
| 1989 | 7 |
| 1990 | 44 |
| 1991 | 40 |
| 1992 | 15 |
| 1993 | 130 |
| 1994 | 132 |
| 1995 | 37 |
| 1996 | 41 |
| 1997 | 23 |
| 1998 | 22 |
| 1999 | 23 |
| 2000 | 29 |
| 2001 | 21 |
| 2002 | 34 |
| 2003 | 65 |
| 2004 | 44 |
| 2005 | 50 |
| 2006 | 68 |
| 2007 | 34 |
| 2008 | 74 |
| 2009 | 98 |
| 2010 | 95 |
| 2011 | 57 |
| 2012 | 93 |
| 2013 | 87 |
| 2014 | 142 |
| 2015 | 162 |
| 2016 | 184 |
| 2017 | 182 |
| 2018 | 138 |
| 2019 | 226 |
| 2020 | 187 |
| 2021 | 217 |
| 2022 | 217 |
| 2023 | 199 |
| 2024 | 251 |