Year	constant 2015 US$
1960	21245850000
1961	25895140000
1962	24966660000
1963	27229430000
1964	27565140000
1965	29944020000
1966	30300510000
1967	30743880000
1968	28779900000
1969	26078090000
1970	26780850000
1971	27123510000
1972	25455750000
1973	28496810000
1974	34900830000
1975	40899230000
1976	38420630000
1977	34825100000
1978	36624940000
1979	36637890000
1980	41647510000
1981	40971630000
1982	40082850000
1983	37848550000
1984	38414420000
1985	40861070000
1986	37697700000
1987	35234670000
1988	36034460000
1989	37915480000
1990	48230170000
1991	50455420000
1992	44419410000
1993	42787920000
1994	43044220000
1995	38179860000
1996	36946680000
1997	34251360000
1998	38069200000
1999	40378620000
2000	38498500000
2001	42491810000
2002	45106790000
2003	41827090000
2004	44233930000
2005	72443530000
2006	63502850000
2007	51630410000
2008	54867970000
2009	53725020000
2010	50315540000
2011	52615690000
2012	51472570000
2013	58716470000
2014	56562910000
2015	58247690000
2016	60186940000
2017	58492300000