| Year | Count |
|---|---|
| 1918 | 8 |
| 1920 | 5 |
| 1925 | 15 |
| 1926 | 25 |
| 1927 | 25 |
| 1928 | 12 |
| 1929 | 20 |
| 1930 | 26 |
| 1932 | 15 |
| 1933 | 13 |
| 1934 | 18 |
| 1935 | 5 |
| 1936 | 26 |
| 1937 | 17 |
| 1938 | 17 |
| 1939 | 12 |
| 1940 | 20 |
| 1941 | 23 |
| 1942 | 22 |
| 1943 | 11 |
| 1944 | 21 |
| 1945 | 24 |
| 1946 | 25 |
| 1947 | 50 |
| 1948 | 35 |
| 1949 | 68 |
| 1950 | 60 |
| 1951 | 128 |
| 1952 | 90 |
| 1953 | 86 |
| 1954 | 69 |
| 1955 | 121 |
| 1956 | 133 |
| 1957 | 162 |
| 1958 | 143 |
| 1959 | 152 |
| 1960 | 159 |
| 1961 | 203 |
| 1962 | 196 |
| 1963 | 301 |
| 1964 | 248 |
| 1965 | 120 |
| 1966 | 116 |
| 1967 | 106 |
| 1968 | 100 |
| 1969 | 87 |
| 1970 | 73 |
| 1971 | 78 |
| 1972 | 68 |
| 1973 | 11 |
| 1977 | 10 |