| Year | Count |
|---|---|
| 1948 | 6 |
| 1951 | 15 |
| 1952 | 20 |
| 1953 | 91 |
| 1954 | 99 |
| 1955 | 62 |
| 1956 | 188 |
| 1957 | 461 |
| 1958 | 527 |
| 1959 | 488 |
| 1960 | 520 |
| 1961 | 408 |
| 1962 | 265 |
| 1963 | 234 |
| 1964 | 254 |
| 1965 | 206 |
| 1966 | 153 |
| 1967 | 147 |
| 1968 | 123 |
| 1969 | 118 |
| 1970 | 147 |
| 1971 | 172 |
| 1972 | 139 |
| 1973 | 67 |
| 1974 | 56 |
| 1975 | 65 |
| 1976 | 45 |
| 1977 | 32 |
| 1978 | 29 |
| 1979 | 33 |
| 1980 | 16 |
| 1981 | 50 |
| 1982 | 27 |
| 1983 | 20 |
| 1984 | 17 |
| 1985 | 19 |
| 1986 | 15 |
| 1987 | 8 |
| 1988 | 7 |
| 1991 | 20 |
| 1995 | 6 |
| 2004 | 10 |