| Year | Count |
|---|---|
| 1945 | 6 |
| 1946 | 6 |
| 1947 | 24 |
| 1948 | 6 |
| 1949 | 7 |
| 1950 | 12 |
| 1951 | 6 |
| 1952 | 8 |
| 1955 | 8 |
| 1956 | 34 |
| 1957 | 44 |
| 1958 | 60 |
| 1959 | 34 |
| 1960 | 39 |
| 1961 | 43 |
| 1962 | 10 |
| 1963 | 75 |
| 1964 | 41 |
| 1965 | 49 |
| 1966 | 39 |
| 1967 | 156 |
| 1968 | 150 |
| 1969 | 107 |
| 1970 | 136 |
| 1971 | 120 |
| 1972 | 73 |
| 1973 | 82 |
| 1974 | 65 |
| 1975 | 60 |
| 1976 | 103 |
| 1977 | 141 |
| 1978 | 258 |
| 1979 | 250 |
| 1980 | 147 |
| 1981 | 172 |
| 1982 | 195 |
| 1983 | 235 |
| 1984 | 177 |
| 1985 | 158 |
| 1986 | 93 |
| 1987 | 130 |
| 1988 | 26 |
| 1989 | 53 |
| 1990 | 59 |
| 1991 | 10 |
| 1992 | 5 |
| 1993 | 5 |
| 1995 | 7 |
| 1996 | 10 |
| 2000 | 6 |
| 2017 | 5 |