| Year | Count |
|---|---|
| 1967 | 22 |
| 1970 | 11 |
| 1973 | 6 |
| 1974 | 13 |
| 1975 | 9 |
| 1976 | 15 |
| 1977 | 12 |
| 1978 | 24 |
| 1979 | 48 |
| 1980 | 45 |
| 1981 | 52 |
| 1982 | 41 |
| 1983 | 68 |
| 1984 | 53 |
| 1985 | 83 |
| 1986 | 46 |
| 1987 | 34 |
| 1988 | 52 |
| 1989 | 43 |
| 1990 | 40 |
| 1991 | 5 |
| 1992 | 10 |
| 1993 | 16 |
| 1994 | 12 |
| 1995 | 10 |
| 1996 | 26 |
| 1997 | 42 |
| 1998 | 77 |
| 1999 | 24 |
| 2000 | 17 |
| 2001 | 6 |
| 2002 | 17 |
| 2003 | 14 |
| 2004 | 42 |
| 2005 | 54 |
| 2006 | 17 |
| 2007 | 40 |
| 2008 | 6 |
| 2010 | 7 |
| 2011 | 15 |
| 2012 | 26 |
| 2015 | 5 |
| 2018 | 5 |
| 2019 | 5 |
| 2021 | 6 |
| 2022 | 8 |
| 2023 | 6 |