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| Year |
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
| 1950 | | | | | | | | | | | | |
| 1951 | | | | | | | | | | | | |
| 1952 | | | | | | | | | | | | |
| 1953 | | | | | | | | | | | | |
| 1954 | | | | | | | | | | | | |
| 1955 | | | | | | | | | | | | |
| 1956 | | | | | | | | | | | | |
| 1957 | | | | | | | | | | | | |
| 1958 | | | | | | | | | | | | |
| 1959 | | | | | | | 5 | | | 12 | 10 | 8 |
| 1960 | 8 | 9 | 8 | | 2 | | 2 | | | 12 | | 26 |
| 1961 | 4 | 2 | 30 | | 30 | 30 | 8 | 33 | 2 | | 4 | 19 |
| 1962 | 10 | 6 | 18 | | 1 | | | | | | 4 | |
| 1963 | 4 | 2 | | 2 | | | | 5 | 2 | 3 | 2 | |
| 1964 | | | | 2 | 1 | 1 | 1 | | | 1 | 2 | 1 |
| 1965 | 3 | 1 | | 1 | 4 | 1 | | 3 | 2 | 3 | | 2 |
| 1966 | 1 | | | | | 1 | | 2 | 3 | 1 | 2 | 2 |
| 1967 | 3 | | 1 | 4 | 7 | 1 | 1 | 2 | 4 | | 2 | |
| 1968 | 1 | | | | 1 | | 5 | 3 | | 1 | 3 | |
| 1969 | 8 | | | | | | | | | | | |
| 1970 | 1 | 3 | 1 | 4 | 8 | 6 | 11 | | 7 | 4 | 6 | 11 |
| 1971 | 15 | 4 | 5 | 1 | 1 | 7 | 8 | | 6 | 1 | 7 | 9 |
| 1972 | 5 | 5 | 1 | | 1 | 3 | | | 3 | 1 | 2 | 4 |
| 1973 | 5 | | | 3 | 1 | 1 | | 3 | 3 | 2 | 1 | |
| 1974 | 4 | 2 | 2 | | 3 | 4 | 1 | | 1 | 2 | 5 | |
| 1975 | | 1 | 2 | | 2 | 1 | 1 | 1 | | 3 | | |
| 1976 | 1 | 1 | 1 | 2 | 4 | | 1 | 4 | 2 | 2 | 1 | |
| 1977 | 5 | 3 | 2 | 1 | | 1 | 2 | 1 | 3 | 1 | 10 | 7 |
| 1978 | 1 | 1 | 2 | 2 | | 1 | 1 | 7 | | 4 | 2 | |
| 1979 | | | 5 | 3 | 1 | 2 | 2 | | | 7 | | 2 |
| 1980 | 6 | 6 | 2 | 2 | 3 | | 3 | | 4 | 3 | 6 | 2 |
| 1981 | 6 | 6 | | 1 | | 1 | | | 5 | 4 | 13 | |
| 1982 | 3 | 4 | 2 | 4 | 3 | 3 | 2 | | | 2 | 2 | 1 |
| 1983 | 2 | | 1 | | | | | | 1 | | 2 | |
| 1984 | | | | 2 | 2 | 1 | 1 | | | | 1 | 1 |
| 1985 | | 1 | 5 | 5 | | 3 | | | 1 | 5 | 1 | 2 |
| 1986 | 1 | 7 | 1 | 1 | 2 | 1 | 3 | 1 | 1 | 1 | 1 | 1 |
| 1987 | 4 | 3 | 5 | | 2 | 3 | | | | | | |
| 1988 | | 1 | 4 | 1 | | | 4 | 3 | 1 | 1 | | |
| 1989 | 1 | | 13 | 5 | 3 | 1 | | 2 | 1 | | | 1 |
| 1990 | | | | 2 | | | | | | | | |