| Year | Count |
|---|---|
| 1963 | 5 |
| 1970 | 6 |
| 1972 | 8 |
| 1974 | 23 |
| 1975 | 17 |
| 1976 | 14 |
| 1977 | 22 |
| 1978 | 24 |
| 1979 | 19 |
| 1981 | 16 |
| 1982 | 6 |
| 1983 | 9 |
| 1984 | 13 |
| 1985 | 13 |
| 1986 | 21 |
| 1987 | 30 |
| 1988 | 22 |
| 1989 | 14 |
| 1990 | 11 |
| 1991 | 43 |
| 1992 | 10 |
| 1993 | 47 |
| 1994 | 44 |
| 1995 | 16 |
| 1996 | 40 |
| 1997 | 31 |
| 1998 | 62 |
| 1999 | 19 |
| 2000 | 45 |
| 2001 | 33 |
| 2002 | 37 |
| 2003 | 28 |
| 2004 | 65 |
| 2005 | 70 |
| 2006 | 37 |
| 2007 | 91 |
| 2008 | 157 |
| 2009 | 62 |
| 2010 | 51 |
| 2011 | 117 |
| 2012 | 47 |
| 2013 | 48 |
| 2014 | 80 |
| 2015 | 84 |
| 2016 | 105 |
| 2017 | 81 |
| 2018 | 76 |
| 2019 | 156 |
| 2020 | 152 |
| 2021 | 102 |
| 2022 | 65 |
| 2023 | 88 |
| 2024 | 47 |