| Year | Count |
|---|---|
| 1921 | 5 |
| 1924 | 7 |
| 1934 | 8 |
| 1938 | 7 |
| 1941 | 5 |
| 1943 | 7 |
| 1950 | 13 |
| 1952 | 9 |
| 1953 | 10 |
| 1954 | 15 |
| 1955 | 34 |
| 1956 | 40 |
| 1957 | 59 |
| 1958 | 31 |
| 1959 | 55 |
| 1960 | 42 |
| 1961 | 45 |
| 1962 | 32 |
| 1963 | 47 |
| 1964 | 60 |
| 1965 | 126 |
| 1966 | 120 |
| 1967 | 75 |
| 1968 | 62 |
| 1969 | 69 |
| 1970 | 28 |
| 1971 | 38 |
| 1972 | 39 |
| 1973 | 20 |
| 1974 | 31 |
| 1975 | 20 |
| 1976 | 20 |
| 1977 | 52 |
| 1978 | 46 |
| 1979 | 69 |
| 1980 | 57 |
| 1981 | 50 |
| 1982 | 70 |
| 1983 | 54 |
| 1984 | 36 |
| 1985 | 34 |
| 1986 | 31 |
| 1987 | 20 |
| 1988 | 16 |
| 1989 | 22 |
| 1990 | 10 |
| 1991 | 5 |
| 1992 | 5 |
| 1994 | 6 |
| 1995 | 5 |
| 1996 | 11 |
| 1997 | 8 |
| 1998 | 13 |
| 2001 | 6 |
| 2003 | 18 |
| 2005 | 10 |
| 2006 | 12 |
| 2007 | 5 |
| 2015 | 6 |
| 2019 | 8 |