| Year | Count |
|---|---|
| 1958 | 12 |
| 1959 | 15 |
| 1960 | 33 |
| 1961 | 46 |
| 1962 | 34 |
| 1963 | 43 |
| 1964 | 65 |
| 1965 | 31 |
| 1966 | 39 |
| 1967 | 92 |
| 1968 | 114 |
| 1969 | 141 |
| 1970 | 120 |
| 1971 | 179 |
| 1972 | 116 |
| 1973 | 127 |
| 1974 | 113 |
| 1975 | 159 |
| 1976 | 171 |
| 1977 | 182 |
| 1978 | 93 |
| 1979 | 88 |
| 1980 | 69 |
| 1981 | 73 |
| 1982 | 90 |
| 1983 | 72 |
| 1984 | 32 |
| 1985 | 49 |
| 1986 | 27 |
| 1987 | 24 |
| 1989 | 16 |
| 1990 | 40 |
| 1992 | 15 |
| 1993 | 6 |