Year	constant 2015 US$
1960	97380000
1961	346600000
1962	394550000
1963	262890000
1964	369700000
1965	287010000
1966	246170000
1967	280500000
1968	275620000
1969	238620000
1970	312870000
1971	348610000
1972	301970000
1973	415210000
1974	605090000
1975	979040000
1976	849350000
1977	1006820000
1978	1099770000
1979	1345130000
1980	1431890000
1981	1586860000
1982	1605540000
1983	1434660000
1984	1408610000
1985	1225970000
1986	1341850000
1987	1538580000
1988	1569760000
1989	1442100000
1990	1620210000
1991	1447870000
1992	1719290000
1993	1284530000
1994	1242030000
1995	995310000
1996	1025160000
1997	1222430000
1998	1294050000
1999	1306330000
2000	1397450000
2001	1728150000
2002	1745510000
2003	2024400000
2004	1897410000
2005	1558430000
2006	1919040000
2007	2719730000
2008	2095140000
2009	2954070000
2010	2791590000
2011	2189630000
2012	2583380000
2013	3139070000
2014	2407170000
2015	2558970000
2016	2317790000
2017	2543180000