| Year | Count |
|---|---|
| 1947 | 5 |
| 1948 | 5 |
| 1952 | 20 |
| 1953 | 6 |
| 1954 | 40 |
| 1955 | 83 |
| 1956 | 71 |
| 1957 | 924 |
| 1958 | 2,013 |
| 1959 | 3,262 |
| 1960 | 2,654 |
| 1961 | 2,676 |
| 1962 | 2,604 |
| 1963 | 2,264 |
| 1964 | 1,892 |
| 1965 | 1,898 |
| 1966 | 1,666 |
| 1967 | 1,651 |
| 1968 | 1,926 |
| 1969 | 1,794 |
| 1970 | 1,770 |
| 1971 | 1,732 |
| 1972 | 1,471 |
| 1973 | 1,146 |
| 1974 | 1,073 |
| 1975 | 930 |
| 1976 | 786 |
| 1977 | 678 |
| 1978 | 680 |
| 1979 | 731 |
| 1980 | 552 |
| 1981 | 481 |
| 1982 | 375 |
| 1983 | 323 |
| 1984 | 277 |
| 1985 | 226 |
| 1986 | 196 |
| 1987 | 116 |
| 1988 | 78 |
| 1989 | 46 |
| 1990 | 51 |
| 1991 | 22 |
| 1994 | 5 |
| 1995 | 6 |
| 1996 | 10 |
| 1997 | 5 |