Year	current US$
1960	53000000
1961	79000000
1962	81500000
1963	99510000
1964	50010000
1965	105480000
1966	138230000
1967	180250000
1968	133000000
1969	152010000
1970	77000000
1971	479270289.345063
1972	818259595.090668
1973	1078479039.8727
1974	8223195945.65258
1975	8743598044.04907
1976	8681248470.72098
1977	12105789030.2728
1978	11977233722.9608
1979	15209641172.7531
1980	10222910262.7425
1981	1605410387.71727
1982	5701205818.24562