| Year | Count |
|---|---|
| 1946 | 6 |
| 1948 | 5 |
| 1949 | 5 |
| 1951 | 5 |
| 1952 | 5 |
| 1953 | 5 |
| 1957 | 5 |
| 1958 | 5 |
| 1960 | 5 |
| 1961 | 5 |
| 1962 | 12 |
| 1966 | 43 |
| 1967 | 17 |
| 1969 | 6 |
| 1970 | 18 |
| 1971 | 11 |
| 1972 | 24 |
| 1973 | 10 |
| 1974 | 6 |
| 1975 | 12 |
| 1976 | 6 |
| 1977 | 42 |
| 1978 | 8 |
| 1979 | 51 |
| 1980 | 93 |
| 1981 | 113 |
| 1982 | 101 |
| 1983 | 126 |
| 1984 | 185 |
| 1985 | 212 |
| 1986 | 167 |
| 1987 | 253 |
| 1988 | 310 |
| 1989 | 244 |
| 1990 | 262 |
| 1991 | 277 |
| 1992 | 177 |
| 1993 | 192 |
| 1994 | 124 |
| 1995 | 48 |
| 1996 | 56 |
| 1997 | 54 |
| 1998 | 64 |
| 1999 | 18 |
| 2000 | 20 |
| 2001 | 16 |
| 2002 | 10 |
| 2003 | 19 |
| 2004 | 30 |
| 2005 | 48 |
| 2006 | 9 |
| 2007 | 19 |
| 2009 | 10 |
| 2010 | 6 |
| 2018 | 5 |