| Year | Count |
|---|---|
| 1931 | 5 |
| 1943 | 12 |
| 1944 | 6 |
| 1945 | 102 |
| 1946 | 80 |
| 1947 | 74 |
| 1948 | 61 |
| 1949 | 113 |
| 1950 | 114 |
| 1951 | 81 |
| 1952 | 114 |
| 1953 | 126 |
| 1954 | 193 |
| 1955 | 194 |
| 1956 | 270 |
| 1957 | 324 |
| 1958 | 390 |
| 1959 | 362 |
| 1960 | 366 |
| 1961 | 323 |
| 1962 | 235 |
| 1963 | 212 |
| 1964 | 154 |
| 1965 | 175 |
| 1966 | 132 |
| 1967 | 127 |
| 1968 | 122 |
| 1969 | 98 |
| 1970 | 64 |
| 1971 | 37 |
| 1972 | 34 |
| 1973 | 14 |
| 1974 | 12 |
| 1975 | 18 |
| 1976 | 13 |
| 1977 | 14 |
| 1979 | 5 |
| 1980 | 13 |
| 1981 | 12 |
| 1982 | 11 |
| 1983 | 12 |
| 1984 | 11 |
| 1985 | 9 |
| 1986 | 16 |
| 1987 | 5 |
| 1988 | 6 |
| 1989 | 8 |
| 1990 | 6 |
| 1991 | 5 |
| 1993 | 5 |
| 1994 | 5 |