Year	current US$
2000	0.5525475922193582
2001	0.5529599083698362
2002	0.6368738386437941
2003	0.8595735488159459
2004	1.5203086390105438
2005	1.5707003863214346
2006	1.660715606388681
2007	2.093427264809552
2008	2.324646023478585
2009	2.3851647519414514
2010	2.6561214944488225
2011	3.0500948332554834
2012	2.9594106831120435
2013	3.237836166067969
2014	3.173804431448088
2015	2.6545295261021615
2016	2.54794429057754
2017	2.550990657816636
2018	2.5396353362736828
2019	2.702243574395187
2020	2.580994893105227
2021	4.1829373776488685