| Year | Count |
|---|---|
| 1950 | 5 |
| 1951 | 10 |
| 1953 | 17 |
| 1954 | 12 |
| 1955 | 24 |
| 1956 | 27 |
| 1957 | 48 |
| 1958 | 42 |
| 1959 | 32 |
| 1960 | 5 |
| 1961 | 6 |
| 1962 | 6 |
| 1963 | 5 |
| 1964 | 7 |
| 1969 | 38 |
| 1970 | 18 |
| 1971 | 18 |
| 1972 | 10 |
| 1973 | 6 |
| 1974 | 11 |
| 1975 | 17 |
| 1976 | 20 |
| 1977 | 33 |
| 1978 | 21 |
| 1979 | 16 |
| 1981 | 5 |
| 1983 | 5 |
| 1988 | 5 |
| 1989 | 10 |
| 1990 | 11 |
| 1991 | 13 |
| 1992 | 5 |
| 1992 | 27 |
| 1993 | 15 |
| 1993 | 16 |
| 1994 | 15 |
| 1995 | 15 |
| 1998 | 10 |
| 2000 | 12 |
| 2002 | 14 |
| 2018 | 10 |