| Year | Count |
|---|---|
| 1955 | 15 |
| 1956 | 10 |
| 1966 | 12 |
| 1967 | 12 |
| 1968 | 10 |
| 1971 | 12 |
| 1972 | 24 |
| 1973 | 9 |
| 1975 | 22 |
| 1976 | 13 |
| 1977 | 5 |
| 1978 | 9 |
| 1979 | 7 |
| 1980 | 7 |
| 1981 | 8 |
| 1982 | 7 |
| 1983 | 21 |
| 1984 | 5 |
| 1985 | 8 |
| 1987 | 10 |
| 1988 | 14 |
| 1989 | 7 |
| 1990 | 24 |
| 1992 | 10 |
| 1993 | 8 |
| 1994 | 22 |
| 1995 | 15 |
| 1996 | 30 |
| 1997 | 42 |
| 1998 | 32 |
| 1999 | 34 |
| 2000 | 39 |
| 2001 | 68 |
| 2002 | 68 |
| 2003 | 61 |
| 2004 | 28 |
| 2005 | 31 |
| 2006 | 30 |
| 2007 | 43 |
| 2008 | 86 |
| 2009 | 5 |
| 2010 | 15 |
| 2011 | 36 |
| 2012 | 18 |
| 2013 | 22 |
| 2014 | 10 |
| 2015 | 20 |
| 2019 | 6 |
| 2023 | 6 |
| 2024 | 6 |