Year	constant 2015 US$
1960	61770000
1961	82040000
1962	30590000
1963	21700000
1964	25060000
1965	39530000
1966	25280000
1967	21380000
1968	33240000
1969	28840000
1970	40730000
1971	30500000
1972	31870000
1973	33410000
1974	52970000
1975	191430000
1976	231750000
1977	265070000
1978	249450000
1979	224350000
1980	235220000
1981	241680000
1982	285380000
1983	297670000
1984	304040000
1985	338080000
1986	348040000
1987	370380000
1988	225480000
1989	319600000
1990	246020000
1991	256200000
1992	141750000
1993	174640000
1994	901110000
1995	964190000
1996	458910000
1997	433520000
1998	550740000
1999	358460000
2000	286580000
2001	239380000
2002	211860000
2003	263430000
2004	341450000
2005	473380000
2006	619440000
2007	707670000
2008	875140000
2009	1085760000
2010	2951630000
2011	1558230000
2012	1186470000
2013	1071620000
2014	993580000
2015	1049350000
2016	1071680000
2017	960110000