Year	constant 2015 US$
1960	2379130000
1961	3775300000
1962	4272280000
1963	4018570000
1964	6113900000
1965	6651680000
1966	6439720000
1967	5967160000
1968	6046840000
1969	5503880000
1970	5484120000
1971	5801750000
1972	5808300000
1973	6150630000
1974	8537790000
1975	10056590000
1976	9031720000
1977	10096730000
1978	11553380000
1979	13075300000
1980	13403150000
1981	14555600000
1982	14992000000
1983	14356010000
1984	14987460000
1985	16398840000
1986	16594710000
1987	16601950000
1988	17232350000
1989	18803480000
1990	19620860000
1991	19407590000
1992	18892810000
1993	17950150000
1994	18590560000
1995	16465090000
1996	14250620000
1997	14196860000
1998	13709960000
1999	12718740000
2000	13755520000
2001	15774920000
2002	21674130000
2003	27520860000
2004	29079340000
2005	54504970000
2006	47178950000
2007	39777750000
2008	39201490000
2009	37663950000
2010	37878960000
2011	37719930000
2012	37407300000
2013	36980820000
2014	35038880000
2015	36853840000
2016	36272250000
2017	40602930000