Year	constant 2015 US$
1960	4490000
1961	8040000
1962	3830000
1963	-90000
1964	3770000
1965	8520000
1966	13600000
1967	20490000
1968	7310000
1969	10810000
1970	18890000
1971	24650000
1972	24590000
1973	34370000
1974	32840000
1975	12600000
1976	13080000
1977	17850000
1978	11520000
1979	16860000
1980	21840000
1981	14960000
1982	6700000
1983	7950000
1984	27780000
1985	72180000
1986	43540000
1987	25900000
1988	25000000
1989	700000
1990	740000
1991	3230000
1992	3850000
1993	-20000
1994	760000
1995	260000
1996	-310000
1997	440000
1998	250000
1999	30000
2000	50000
2001	1100000
2002	20000
2003	40000
2004	200000