| Year | Count |
|---|---|
| 1941 | 5 |
| 1942 | 17 |
| 1943 | 18 |
| 1944 | 12 |
| 1945 | 15 |
| 1946 | 24 |
| 1947 | 30 |
| 1948 | 27 |
| 1949 | 31 |
| 1950 | 26 |
| 1951 | 24 |
| 1952 | 10 |
| 1953 | 29 |
| 1954 | 26 |
| 1955 | 276 |
| 1956 | 93 |
| 1957 | 78 |
| 1958 | 53 |
| 1959 | 38 |
| 1960 | 40 |
| 1961 | 39 |
| 1962 | 17 |
| 1963 | 19 |
| 1964 | 35 |
| 1965 | 8 |
| 1966 | 70 |
| 1967 | 161 |
| 1968 | 56 |
| 1969 | 43 |
| 1970 | 29 |
| 1971 | 46 |
| 1972 | 27 |
| 1973 | 11 |
| 1974 | 15 |
| 1976 | 11 |
| 1977 | 37 |
| 1978 | 41 |
| 1979 | 26 |
| 1980 | 5 |
| 1981 | 11 |
| 1982 | 6 |
| 1983 | 18 |
| 1984 | 7 |
| 1984 | 7 |
| 1985 | 12 |
| 1986 | 15 |
| 1987 | 28 |
| 1989 | 18 |
| 1992 | 11 |
| 1993 | 6 |
| 1995 | 18 |
| 1998 | 5 |
| 2003 | 10 |
| 2003 | 8 |
| 2004 | 7 |
| 2005 | 7 |
| 2005 | 5 |
| 2006 | 5 |
| 2006 | 5 |
| 2007 | 27 |
| 2008 | 7 |