Year	current US$
2000	1.18528352
2001	3.41217841
2002	5.71966653
2003	7.32126886
2004	6.72321115
2005	7.17305395
2006	7.47815914
2007	8.25015104
2008	7.1207228
2009	8.37594299
2010	10.30484703
2011	11.89090256
2012	15.88696656
2013	21.0333443
2014	28.95052448
2015	5.40495342
2016	9.70938515
2017	8.67284041
2018	12.00396426
2019	19.38918729
2020	11.73907114
2021	24.34811156