| Year | Count |
|---|---|
| 1935 | 5 |
| 1937 | 12 |
| 1938 | 34 |
| 1939 | 14 |
| 1940 | 22 |
| 1941 | 34 |
| 1942 | 34 |
| 1943 | 81 |
| 1944 | 24 |
| 1945 | 44 |
| 1946 | 136 |
| 1947 | 201 |
| 1948 | 216 |
| 1949 | 253 |
| 1950 | 255 |
| 1951 | 339 |
| 1952 | 355 |
| 1953 | 618 |
| 1954 | 841 |
| 1955 | 515 |
| 1956 | 494 |
| 1957 | 459 |
| 1958 | 405 |
| 1959 | 606 |
| 1960 | 555 |
| 1961 | 641 |
| 1962 | 594 |
| 1963 | 415 |
| 1964 | 386 |
| 1965 | 394 |
| 1966 | 359 |
| 1967 | 276 |
| 1968 | 290 |
| 1969 | 241 |
| 1970 | 231 |
| 1971 | 241 |
| 1972 | 142 |
| 1973 | 69 |
| 1974 | 67 |
| 1975 | 53 |
| 1976 | 50 |
| 1977 | 70 |
| 1978 | 29 |
| 1979 | 43 |
| 1980 | 16 |
| 1981 | 19 |
| 1982 | 18 |
| 1983 | 9 |
| 1985 | 10 |
| 1986 | 10 |
| 1987 | 27 |
| 1988 | 7 |
| 1995 | 11 |
| 1997 | 5 |