| Year | Count |
|---|---|
| 1915 | 5 |
| 1919 | 10 |
| 1921 | 6 |
| 1923 | 13 |
| 1925 | 6 |
| 1926 | 6 |
| 1927 | 6 |
| 1928 | 10 |
| 1929 | 49 |
| 1930 | 71 |
| 1931 | 75 |
| 1932 | 68 |
| 1933 | 71 |
| 1934 | 108 |
| 1935 | 96 |
| 1936 | 82 |
| 1937 | 103 |
| 1938 | 112 |
| 1939 | 141 |
| 1940 | 131 |
| 1941 | 181 |
| 1942 | 204 |
| 1943 | 169 |
| 1944 | 107 |
| 1945 | 147 |
| 1946 | 165 |
| 1947 | 173 |
| 1948 | 112 |
| 1949 | 116 |
| 1950 | 192 |
| 1951 | 279 |
| 1952 | 284 |
| 1953 | 316 |
| 1954 | 397 |
| 1955 | 220 |
| 1956 | 166 |
| 1957 | 134 |
| 1958 | 82 |
| 1959 | 81 |
| 1960 | 70 |
| 1961 | 72 |
| 1962 | 56 |
| 1963 | 50 |
| 1964 | 82 |
| 1965 | 36 |
| 1966 | 74 |
| 1967 | 43 |
| 1968 | 48 |
| 1969 | 58 |
| 1970 | 99 |
| 1971 | 82 |
| 1972 | 52 |
| 1973 | 37 |
| 1974 | 26 |
| 1975 | 39 |
| 1976 | 21 |
| 1977 | 5 |
| 1978 | 21 |
| 1979 | 23 |
| 1982 | 5 |
| 1986 | 11 |
| 1987 | 5 |
| 1988 | 15 |
| 1993 | 6 |