| Year | Count |
|---|---|
| 1920 | 6 |
| 1929 | 10 |
| 1938 | 6 |
| 1942 | 12 |
| 1943 | 7 |
| 1944 | 10 |
| 1945 | 14 |
| 1946 | 16 |
| 1947 | 16 |
| 1948 | 30 |
| 1949 | 25 |
| 1950 | 38 |
| 1951 | 66 |
| 1952 | 85 |
| 1953 | 91 |
| 1954 | 88 |
| 1955 | 102 |
| 1956 | 118 |
| 1957 | 212 |
| 1958 | 202 |
| 1959 | 188 |
| 1960 | 156 |
| 1961 | 162 |
| 1963 | 71 |
| 1964 | 59 |
| 1965 | 68 |
| 1966 | 49 |
| 1967 | 47 |
| 1968 | 41 |
| 1969 | 53 |
| 1970 | 45 |
| 1971 | 37 |
| 1972 | 22 |
| 1973 | 25 |
| 1974 | 20 |
| 1975 | 15 |
| 1976 | 20 |
| 1977 | 26 |
| 1978 | 34 |
| 1979 | 22 |
| 1980 | 32 |
| 1981 | 5 |
| 1982 | 7 |
| 1984 | 6 |
| 1985 | 5 |
| 1987 | 5 |
| 1988 | 8 |
| 1993 | 5 |
| 2000 | 5 |
| 2011 | 5 |