Year	constant 2015 US$
1960	282040000
1961	189260000
1962	257540000
1963	245250000
1964	233150000
1965	362130000
1966	302120000
1967	377790000
1968	432070000
1969	424380000
1970	448650000
1971	345370000
1972	275280000
1973	268020000
1974	285100000
1975	309550000
1976	572400000
1977	407040000
1978	657710000
1979	905390000
1980	918520000
1981	888210000
1982	900420000
1983	961560000
1984	1048840000
1985	1048260000
1986	811300000
1987	689530000
1988	694890000
1989	909240000
1990	1044340000
1991	888930000
1992	856560000
1993	647210000
1994	586730000
1995	731280000
1996	792840000
1997	666680000
1998	782310000
1999	1007640000
2000	668460000
2001	329540000
2002	343290000
2003	-922760000
2004	66470000
2005	-146170000
2006	-227680000
2007	-340400000
2008	-577620000
2009	-54130000
2010	5870000
2011	-95680000
2012	-78740000
2013	24500000
2014	336830000
2015	48850000
2016	227780000
2017	250180000