Year	current US$
2000	50.42418107
2001	58.15015912
2002	64.10520232
2003	70.7842681
2004	90.0186923
2005	109.06943518
2006	115.18446628
2007	147.2902009
2008	187.03321072
2009	230.84497334
2010	295.00109837
2011	345.74959169
2012	337.2675769
2013	251.13882398
2014	186.22915439
2015	195.94391455
2016	246.10382371
2017	251.85533875
2018	265.79048837
2019	210.12400866
2020	164.28348543
2021	174.76171535