| Year | Count |
|---|---|
| 1914 | 10 |
| 1915 | 27 |
| 1917 | 25 |
| 1918 | 28 |
| 1919 | 52 |
| 1920 | 57 |
| 1921 | 62 |
| 1922 | 62 |
| 1923 | 99 |
| 1924 | 93 |
| 1925 | 128 |
| 1926 | 138 |
| 1927 | 201 |
| 1928 | 208 |
| 1929 | 207 |
| 1930 | 264 |
| 1931 | 328 |
| 1932 | 314 |
| 1933 | 401 |
| 1934 | 452 |
| 1935 | 427 |
| 1936 | 452 |
| 1937 | 460 |
| 1938 | 445 |
| 1939 | 437 |
| 1940 | 377 |
| 1941 | 354 |
| 1942 | 328 |
| 1943 | 330 |
| 1944 | 227 |
| 1945 | 247 |
| 1946 | 243 |
| 1947 | 288 |
| 1948 | 236 |
| 1949 | 216 |
| 1950 | 216 |
| 1951 | 221 |
| 1952 | 191 |
| 1953 | 217 |
| 1954 | 171 |
| 1955 | 111 |
| 1956 | 130 |
| 1957 | 112 |
| 1958 | 88 |
| 1959 | 105 |
| 1960 | 70 |
| 1961 | 69 |
| 1962 | 52 |
| 1963 | 45 |
| 1964 | 65 |
| 1965 | 9 |
| 1967 | 19 |
| 1968 | 10 |
| 1969 | 5 |