Year	constant 2015 US$
1975	99650000
1976	191573000
1977	153641000
1978	100869000
1979	65573000
1980	147330000
1981	139319000
1982	181844000
1983	151177000
1984	178011000
1985	194474000
1986	165752000
1987	79135000
1988	120502000
1989	39826000
1990	18040000
1991	16196000
1992	489000
2003	25530000
2004	72598000
2005	99913000
2006	151619000
2007	86917000
2008	81840000
2009	98729000
2010	97347000
2011	112550000
2012	103183000
2013	107916000
2014	122082000
2015	155550000
2016	200390000