| Year | Count |
|---|---|
| 1952 | 5 |
| 1953 | 6 |
| 1954 | 9 |
| 1955 | 38 |
| 1956 | 52 |
| 1957 | 123 |
| 1958 | 115 |
| 1959 | 125 |
| 1960 | 163 |
| 1961 | 182 |
| 1962 | 108 |
| 1963 | 131 |
| 1964 | 157 |
| 1965 | 67 |
| 1966 | 68 |
| 1967 | 82 |
| 1968 | 40 |
| 1969 | 99 |
| 1970 | 140 |
| 1971 | 122 |
| 1972 | 119 |
| 1973 | 109 |
| 1974 | 33 |
| 1975 | 47 |
| 1976 | 33 |
| 1977 | 58 |
| 1978 | 41 |
| 1979 | 61 |
| 1980 | 21 |
| 1981 | 40 |
| 1982 | 12 |
| 1983 | 17 |
| 1985 | 23 |
| 1987 | 10 |
| 1988 | 7 |
| 1989 | 5 |
| 1991 | 5 |
| 1997 | 10 |
| 2001 | 5 |