| Year | Count |
|---|---|
| 1954 | 5 |
| 1955 | 10 |
| 1957 | 5 |
| 1958 | 7 |
| 1959 | 40 |
| 1960 | 39 |
| 1961 | 28 |
| 1962 | 17 |
| 1963 | 18 |
| 1965 | 20 |
| 1967 | 10 |
| 1968 | 54 |
| 1969 | 38 |
| 1970 | 52 |
| 1971 | 97 |
| 1972 | 112 |
| 1973 | 105 |
| 1974 | 47 |
| 1975 | 43 |
| 1976 | 88 |
| 1977 | 64 |
| 1978 | 38 |
| 1979 | 15 |
| 1980 | 23 |
| 1981 | 18 |
| 1982 | 25 |
| 1983 | 13 |
| 1984 | 12 |
| 1985 | 10 |
| 1986 | 18 |
| 1987 | 10 |