| Year | Count |
|---|---|
| 1948 | 11 |
| 1949 | 15 |
| 1950 | 28 |
| 1951 | 41 |
| 1952 | 74 |
| 1953 | 78 |
| 1954 | 84 |
| 1955 | 136 |
| 1956 | 134 |
| 1957 | 259 |
| 1958 | 289 |
| 1959 | 397 |
| 1960 | 379 |
| 1961 | 403 |
| 1962 | 86 |
| 1963 | 176 |
| 1964 | 142 |
| 1965 | 131 |
| 1966 | 172 |
| 1967 | 164 |
| 1968 | 139 |
| 1969 | 118 |
| 1970 | 114 |
| 1971 | 82 |
| 1972 | 88 |
| 1973 | 83 |
| 1974 | 62 |
| 1975 | 52 |
| 1976 | 49 |
| 1977 | 95 |
| 1978 | 38 |
| 1979 | 55 |
| 1980 | 44 |
| 1981 | 21 |
| 1982 | 32 |
| 1983 | 25 |
| 1984 | 24 |
| 1985 | 7 |
| 1986 | 22 |
| 1987 | 13 |
| 1988 | 6 |
| 1989 | 9 |
| 1990 | 13 |
| 1991 | 22 |
| 1992 | 20 |
| 1993 | 16 |
| 1994 | 6 |
| 2005 | 10 |