| Year | Count |
|---|---|
| 1949 | 5 |
| 1950 | 17 |
| 1951 | 36 |
| 1952 | 30 |
| 1953 | 20 |
| 1954 | 20 |
| 1955 | 40 |
| 1956 | 37 |
| 1957 | 39 |
| 1958 | 49 |
| 1959 | 24 |
| 1960 | 81 |
| 1961 | 64 |
| 1962 | 51 |
| 1963 | 24 |
| 1964 | 67 |
| 1965 | 31 |
| 1966 | 37 |
| 1967 | 32 |
| 1968 | 45 |
| 1969 | 75 |
| 1970 | 60 |
| 1971 | 119 |
| 1972 | 53 |
| 1973 | 42 |
| 1974 | 43 |
| 1975 | 26 |
| 1976 | 5 |
| 1977 | 24 |
| 1978 | 24 |
| 1979 | 7 |
| 1980 | 9 |
| 1981 | 11 |
| 1982 | 5 |
| 1984 | 6 |
| 1988 | 10 |
| 1990 | 24 |
| 1993 | 5 |
| 1995 | 10 |
| 1997 | 10 |