Year	current US$
2003	1.0380087265766107
2004	1.7131052878623356
2005	1.4639087694035375
2006	1.5583454752925985
2007	2.089444731199258
2008	1.6417213225858338
2009	2.0081454748670047
2010	1.5484362609488602
2011	1.7345864241827733
2012	1.7815307911404352
2013	1.6942416757505443
2014	2.616171121791455
2015	2.0501584608395094
2016	2.0238142899564733
2017	1.8547958140476273
2018	1.7830835593942012
2019	2.3818055131329054
2020	2.5737226882608675
2021	3.857140785235546