Year	constant 2015 US$
1960	6344280000
1961	5988590000
1962	6280860000
1963	6107090000
1964	5378210000
1965	7434540000
1966	8366090000
1967	9749260000
1968	9825180000
1969	10391720000
1970	10378090000
1971	11286440000
1972	11585150000
1973	10612710000
1974	11334960000
1975	8993420000
1976	7595820000
1977	7034640000
1978	7985790000
1979	8367680000
1980	8684530000
1981	9855180000
1982	9308320000
1983	9408050000
1984	9667910000
1985	9940350000
1986	9815140000
1987	9883770000
1988	10379320000
1989	11085040000
1990	11412390000
1991	10437140000
1992	12374550000
1993	12041350000
1994	11719200000
1995	11185420000
1996	9691240000
1997	9252930000
1998	11442870000
1999	12258240000
2000	11451720000
2001	10837050000
2002	10667450000
2003	9242900000
2004	8819100000
2005	10273420000
2006	8450640000
2007	8563880000
2008	8249950000
2009	9718290000
2010	8958330000
2011	6812580000
2012	7762920000
2013	10612220000
2014	8373800000
2015	8466560000
2016	7705750000
2017	7984140000