Year	current US$
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	0
1989	0
1990	0
1991	0
1992	8131.58644681647
1993	1388.65777951578
1994	28225.4315532658
1995	606.03344695499
1996	0
1997	0
1998	0
1999	0
2000	0
2001	0
2002	0
2003	0
2004	0
2005	0
2006	0
2007	0
2008	0
2009	265.797535460556
2010	743.118830823997
2011	3217.5518122207
2012	4637.99385491996
2013	5703.82950957587
2014	5814.72934047943
2015	7124.15942350869
2016	6144.99817280223
2017	10812.655168873
2018	20840.282333246
2019	0
2020	0
2021	0