| Year | Count |
|---|---|
| 1939 | 6 |
| 1940 | 5 |
| 1941 | 7 |
| 1942 | 8 |
| 1943 | 15 |
| 1944 | 18 |
| 1945 | 24 |
| 1946 | 38 |
| 1947 | 40 |
| 1948 | 42 |
| 1949 | 46 |
| 1950 | 27 |
| 1951 | 23 |
| 1952 | 27 |
| 1953 | 27 |
| 1954 | 22 |
| 1955 | 21 |
| 1956 | 27 |
| 1957 | 34 |
| 1958 | 52 |
| 1959 | 34 |
| 1960 | 26 |
| 1961 | 32 |
| 1963 | 20 |
| 1964 | 14 |
| 1965 | 12 |
| 1966 | 8 |
| 1967 | 13 |
| 1968 | 14 |
| 1969 | 12 |
| 1970 | 13 |
| 1971 | 14 |
| 1973 | 5 |
| 1980 | 5 |
| 1981 | 5 |
| 1991 | 8 |
| 1994 | 5 |
| 1999 | 5 |