| Year | Count |
|---|---|
| 1915 | 6 |
| 1917 | 6 |
| 1918 | 9 |
| 1919 | 5 |
| 1920 | 8 |
| 1921 | 8 |
| 1922 | 28 |
| 1923 | 12 |
| 1924 | 10 |
| 1925 | 18 |
| 1926 | 16 |
| 1927 | 32 |
| 1928 | 14 |
| 1929 | 20 |
| 1931 | 6 |
| 1932 | 5 |
| 1933 | 5 |
| 1935 | 5 |
| 1936 | 5 |
| 1937 | 9 |
| 1938 | 5 |
| 1939 | 5 |
| 1940 | 5 |
| 1941 | 7 |
| 1942 | 8 |
| 1943 | 10 |
| 1944 | 5 |
| 1946 | 9 |
| 1947 | 9 |
| 1948 | 6 |
| 1949 | 6 |
| 1950 | 6 |
| 1951 | 14 |
| 1952 | 6 |
| 1953 | 12 |
| 1954 | 13 |
| 1955 | 8 |
| 1956 | 11 |
| 1957 | 16 |
| 1958 | 10 |
| 1959 | 26 |
| 1960 | 30 |
| 1961 | 42 |
| 1963 | 18 |
| 1964 | 14 |
| 1965 | 10 |
| 1966 | 11 |
| 1967 | 13 |
| 1968 | 11 |
| 1969 | 6 |
| 1970 | 6 |
| 1971 | 7 |