| Year | Count |
|---|---|
| 1914 | 15 |
| 1919 | 10 |
| 1920 | 5 |
| 1921 | 6 |
| 1922 | 6 |
| 1923 | 5 |
| 1924 | 11 |
| 1926 | 25 |
| 1940 | 5 |
| 1951 | 10 |
| 1956 | 10 |
| 1957 | 15 |
| 1958 | 15 |
| 1960 | 7 |
| 1961 | 20 |
| 1962 | 12 |
| 1963 | 45 |
| 1964 | 60 |
| 1965 | 124 |
| 1966 | 194 |
| 1967 | 253 |
| 1968 | 292 |
| 1969 | 300 |
| 1970 | 306 |
| 1971 | 332 |
| 1972 | 312 |
| 1973 | 293 |
| 1974 | 218 |
| 1975 | 215 |
| 1976 | 178 |
| 1977 | 227 |
| 1978 | 204 |
| 1979 | 296 |
| 1980 | 126 |
| 1981 | 162 |
| 1982 | 128 |
| 1983 | 137 |
| 1984 | 105 |
| 1985 | 92 |
| 1986 | 87 |
| 1987 | 123 |
| 1988 | 96 |
| 1989 | 108 |
| 1990 | 73 |
| 1991 | 32 |
| 1992 | 55 |
| 1993 | 23 |
| 1994 | 46 |
| 1995 | 5 |
| 1996 | 26 |
| 1997 | 27 |
| 1998 | 8 |