1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 | 0.000 0.003 0.016 0.133 0.263 0.209 0.217 1.175 1.119 2.240 1.470 0.891 0.164 | 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 | 0.038 0.083 0.276 0.408 0.594 0.360 0.333 0.313 0.335 0.416 0.407 0.362 0.354 | 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 | 0.435 0.451 0.525 0.629 0.654 0.751 0.931 1.148 1.436 3.760 5.287 5.227 4.579 | 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 | 4.339 4.099 3.621 2.770 3.054 3.468 3.065 2.801 3.556 3.556 3.536 5.475 |