| Year | Count |
|---|---|
| 1928 | 15 |
| 1931 | 5 |
| 1932 | 6 |
| 1933 | 10 |
| 1934 | 38 |
| 1935 | 20 |
| 1936 | 34 |
| 1937 | 34 |
| 1938 | 23 |
| 1939 | 7 |
| 1940 | 46 |
| 1941 | 45 |
| 1942 | 60 |
| 1943 | 43 |
| 1944 | 37 |
| 1945 | 45 |
| 1946 | 39 |
| 1947 | 15 |
| 1948 | 12 |
| 1949 | 6 |
| 1950 | 34 |
| 1951 | 58 |
| 1952 | 48 |
| 1953 | 275 |
| 1954 | 239 |
| 1955 | 191 |
| 1956 | 135 |
| 1957 | 201 |
| 1958 | 220 |
| 1959 | 169 |
| 1960 | 227 |
| 1961 | 194 |
| 1962 | 102 |
| 1963 | 116 |
| 1964 | 78 |
| 1965 | 47 |
| 1966 | 44 |
| 1967 | 26 |
| 1968 | 42 |
| 1969 | 33 |
| 1970 | 14 |
| 1971 | 8 |
| 1972 | 17 |
| 1973 | 6 |
| 1974 | 6 |
| 1975 | 8 |
| 1976 | 17 |
| 1979 | 5 |