Year	constant 2015 US$
1960	132050000
1961	204280000
1962	209830000
1963	266450000
1964	70880000
1965	-512730000
1966	-103810000
1967	148390000
1968	211010000
1969	136990000
1970	35820000
1971	150270000
1972	109950000
1973	196510000
1974	138850000
1975	89590000
1976	101690000
1977	83250000
1978	70570000
1979	96030000
1980	37430000
1981	99360000
1982	71570000
1983	112420000
1984	119390000
1985	98080000
1986	160960000
1987	157370000
1988	231240000
1989	328350000
1990	223440000
1991	349140000
1992	313390000
1993	306050000
1994	192520000
1995	150040000
1996	152450000
1997	126660000
1998	104260000
1999	95260000
2000	64320000
2001	225330000
2002	125400000
2003	129010000
2004	97120000
2005	97530000
2006	111300000
2007	81300000
2008	103520000
2009	99350000
2010	112680000
2011	82860000
2012	160370000
2013	31870000
2014	43310000
2015	-17360000
2016	2620000
2017	-4790000