Year	current US$
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0
1988	0
1989	0
1990	0
1991	0
1992	0
1993	0
1994	0
1995	0
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	0
2010	35699.0447720998
2011	33942.58001623813
2012	31174.85496054604
2013	27810.54245937026
2014	23961.874548947664
2015	23525.9753116533
2016	23056.069039830927
2017	21455.125671360383
2018	20767.663817045523
2019	19975.046772071393
2020	19416.84986464514
2021	19093.899021915022
2022	23516.642547033283
2023	12401.472995090016