| Year | Count |
|---|---|
| 1946 | 12 |
| 1947 | 57 |
| 1948 | 14 |
| 1949 | 16 |
| 1950 | 17 |
| 1951 | 18 |
| 1952 | 18 |
| 1953 | 30 |
| 1954 | 45 |
| 1955 | 90 |
| 1956 | 112 |
| 1957 | 133 |
| 1958 | 109 |
| 1959 | 154 |
| 1960 | 169 |
| 1961 | 176 |
| 1962 | 130 |
| 1963 | 149 |
| 1964 | 105 |
| 1965 | 142 |
| 1966 | 130 |
| 1967 | 72 |
| 1968 | 100 |
| 1969 | 122 |
| 1970 | 129 |
| 1971 | 127 |
| 1972 | 106 |
| 1973 | 118 |
| 1974 | 47 |
| 1975 | 63 |
| 1976 | 53 |
| 1977 | 66 |
| 1978 | 39 |
| 1979 | 39 |
| 1980 | 34 |
| 1981 | 9 |
| 1982 | 22 |
| 1983 | 7 |
| 1984 | 11 |
| 1985 | 10 |
| 1986 | 10 |
| 1987 | 22 |
| 1988 | 9 |
| 2011 | 5 |