| Year | Count |
|---|---|
| 1934 | 5 |
| 1935 | 29 |
| 1936 | 7 |
| 1937 | 7 |
| 1939 | 8 |
| 1940 | 16 |
| 1941 | 12 |
| 1943 | 5 |
| 1946 | 5 |
| 1950 | 24 |
| 1952 | 11 |
| 1953 | 12 |
| 1954 | 15 |
| 1955 | 24 |
| 1956 | 36 |
| 1957 | 24 |
| 1958 | 19 |
| 1959 | 22 |
| 1960 | 50 |
| 1961 | 15 |
| 1962 | 15 |
| 1963 | 33 |
| 1964 | 82 |
| 1965 | 10 |
| 1967 | 31 |
| 1968 | 21 |
| 1970 | 42 |
| 1971 | 27 |
| 1972 | 35 |
| 1973 | 45 |
| 1974 | 24 |
| 1975 | 9 |
| 1976 | 12 |
| 1977 | 16 |
| 1978 | 34 |
| 1979 | 41 |
| 1980 | 21 |
| 1981 | 11 |