Year	constant 2015 US$
1960	4001340000
1961	3740050000
1962	4241410000
1963	3807800000
1964	3906480000
1965	5409960000
1966	6122630000
1967	7328440000
1968	7541890000
1969	7614580000
1970	8014470000
1971	8616710000
1972	8916250000
1973	8576110000
1974	9639300000
1975	7429500000
1976	6199580000
1977	5450700000
1978	6723910000
1979	7090360000
1980	7385900000
1981	8121440000
1982	8052610000
1983	8145340000
1984	8421630000
1985	8729560000
1986	8473120000
1987	8556880000
1988	9142230000
1989	9630270000
1990	10412530000
1991	9453750000
1992	11563170000
1993	10947210000
1994	10803260000
1995	10132250000
1996	8907370000
1997	8505790000
1998	10503480000
1999	11413780000
2000	10478880000
2001	9902810000
2002	9688780000
2003	8562690000
2004	7720980000
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