Year	constant 2015 US$
1960	8780000
1961	8410000
1962	52360000
1963	47350000
1964	178460000
1965	89000000
1966	220990000
1967	475320000
1968	246400000
1969	151220000
1970	86500000
1971	129830000
1972	115410000
1973	209410000
1974	234540000
1975	302990000
1976	216280000
1977	333070000
1978	495970000
1979	667730000
1980	676870000
1981	518000000
1982	736140000
1983	511000000
1984	581380000
1985	778130000
1986	880300000
1987	716590000
1988	723350000
1989	566140000
1990	655050000
1991	1158420000
1992	1304970000
1993	1150260000
1994	905420000
1995	2312840000
1996	722600000
1997	787080000
1998	458320000
1999	801990000
2000	1097740000
2001	802580000
2002	1098200000
2003	905800000
2004	1185240000
2005	1210100000
2006	1526950000
2007	977190000
2008	1017140000
2009	1200290000
2010	876980000
2011	935360000
2012	891340000
2013	1043140000
2014	914340000
2015	794610000
2016	964470000
2017	1007590000