Year current US$ 1960 5000000 1961 6000000 1962 8000000 1963 17000000 1964 11000000 1965 18159999.8474121 1966 17959999.084472697 1967 20100000.3814697 1968 29909999.8474121 1969 46000000 1970 48000000 1971 53000000 1972 57000000 1973 63000000 1974 73000000 1975 79000000 1976 89000000 1977 91000000 1978 100000000 1979 111000000 1980 108000000 1981 133000000 1982 157000000 1983 130000000 1984 178000000 1985 154000000 1986 219000000 1987 173000000 1988 147000000 1989 156000000 1990 52000000 1991 5000000 1993 83000000