Year	constant 2015 US$
1960	768280000
1961	1052110000
1962	1325090000
1963	784980000
1964	523000000
1965	404240000
1966	672040000
1967	1816110000
1968	2291600000
1969	2123040000
1970	2904690000
1971	3361660000
1972	2551800000
1973	2668040000
1974	2590220000
1975	2440510000
1976	2270090000
1977	1565900000
1978	1621330000
1979	1732210000
1980	2086660000
1981	2172580000
1982	2090360000
1983	1710050000
1984	1592680000
1985	1444110000
1986	1353040000
1987	1847710000
1988	2172080000
1989	2509730000
1990	2286150000
1991	2248960000
1992	2213000000
1993	2120870000
1994	1615890000
1995	1240130000
1996	1038690000
1997	913140000
1998	1488000000
1999	2265810000
2000	1920200000
2001	1810540000
2002	1668090000
2003	1961220000
2004	237650000
2005	2635710000
2006	1415760000
2007	834890000
2008	1093510000
2009	1075500000
2010	1274400000
2011	392940000
2012	105930000
2013	-18150000
2014	-486220000
2015	-147830000
2016	-110840000
2017	158180000