| Year | Count |
|---|---|
| 1934 | 5 |
| 1939 | 5 |
| 1940 | 7 |
| 1944 | 6 |
| 1946 | 6 |
| 1947 | 9 |
| 1948 | 12 |
| 1949 | 9 |
| 1950 | 10 |
| 1951 | 10 |
| 1952 | 11 |
| 1953 | 16 |
| 1954 | 13 |
| 1955 | 16 |
| 1956 | 16 |
| 1957 | 32 |
| 1958 | 30 |
| 1959 | 44 |
| 1960 | 30 |
| 1961 | 42 |
| 1963 | 14 |
| 1964 | 12 |
| 1965 | 8 |
| 1966 | 14 |
| 1967 | 17 |
| 1968 | 18 |
| 1969 | 13 |
| 1970 | 14 |
| 1971 | 16 |
| 1972 | 18 |
| 1973 | 12 |
| 1974 | 12 |
| 1975 | 10 |
| 1976 | 10 |
| 1977 | 10 |
| 1978 | 18 |
| 1982 | 8 |
| 1983 | 5 |
| 1987 | 6 |
| 1988 | 8 |
| 1990 | 5 |
| 1991 | 6 |
| 1992 | 8 |
| 1995 | 9 |
| 1997 | 6 |