| Year | Count |
|---|---|
| 1953 | 19 |
| 1954 | 59 |
| 1955 | 39 |
| 1956 | 44 |
| 1957 | 75 |
| 1958 | 65 |
| 1959 | 61 |
| 1960 | 87 |
| 1961 | 96 |
| 1962 | 47 |
| 1963 | 79 |
| 1964 | 79 |
| 1965 | 89 |
| 1966 | 76 |
| 1967 | 118 |
| 1968 | 132 |
| 1969 | 128 |
| 1970 | 154 |
| 1971 | 170 |
| 1972 | 82 |
| 1973 | 140 |
| 1974 | 79 |
| 1975 | 74 |
| 1976 | 52 |
| 1977 | 80 |
| 1978 | 97 |
| 1979 | 111 |
| 1980 | 97 |
| 1981 | 61 |
| 1982 | 87 |
| 1983 | 70 |
| 1984 | 79 |
| 1985 | 48 |
| 1986 | 58 |
| 1987 | 23 |
| 1988 | 29 |
| 1989 | 16 |
| 1990 | 38 |
| 1991 | 18 |
| 1992 | 17 |
| 1993 | 11 |
| 1994 | 13 |
| 1995 | 5 |
| 1996 | 7 |
| 1997 | 7 |
| 1998 | 5 |
| 1999 | 7 |