| Year | Count |
|---|---|
| 1955 | 5 |
| 1956 | 12 |
| 1957 | 49 |
| 1958 | 13 |
| 1959 | 37 |
| 1960 | 47 |
| 1961 | 59 |
| 1962 | 41 |
| 1963 | 19 |
| 1964 | 23 |
| 1965 | 16 |
| 1966 | 33 |
| 1967 | 41 |
| 1968 | 12 |
| 1969 | 16 |
| 1970 | 38 |
| 1971 | 63 |
| 1972 | 37 |
| 1973 | 62 |
| 1974 | 63 |
| 1975 | 41 |
| 1976 | 19 |
| 1977 | 25 |
| 1978 | 5 |
| 1979 | 6 |
| 1980 | 7 |
| 1981 | 10 |
| 1982 | 5 |
| 1983 | 15 |
| 1984 | 7 |
| 1988 | 5 |
| 1998 | 30 |
| 2007 | 5 |
| 2010 | 5 |