Year	constant 2015 US$
1960	6557400000
1961	7676150000
1962	6777190000
1963	5837740000
1964	5269370000
1965	4194320000
1966	3744690000
1967	2951200000
1968	2706520000
1969	2796660000
1970	4038930000
1971	3645390000
1972	3656590000
1973	8619220000
1974	12744970000
1975	17084430000
1976	16607680000
1977	17988640000
1978	16292670000
1979	15530510000
1980	16519760000
1981	16154750000
1982	13074760000
1983	10609890000
1984	10413490000
1985	11018100000
1986	8486810000
1987	8376500000
1988	5982030000
1989	5986850000
1990	15924150000
1991	14442270000
1992	8999890000
1993	7091310000
1994	7408370000
1995	5515830000
1996	6032550000
1997	5989550000
1998	6201820000
1999	5605960000
2000	5147310000
2001	5448780000
2002	4653920000
2003	8399570000
2004	10314900000
2005	28852690000
2006	14613640000
2007	14439290000
2008	15332580000
2009	7797680000
2010	6717160000
2011	7311550000
2012	9399350000
2013	15264360000
2014	15662740000
2015	16223260000
2016	22756540000
2017	24643120000