Year	current US$
2000	42.058776307602095
2001	41.02774201491078
2002	41.39226155094765
2003	39.28594517489197
2004	42.80099032524313
2005	46.99299555021946
2006	52.57270057816387
2007	62.1939708237404
2008	72.51062467360673
2009	71.9822069013939
2010	77.38695691133287
2011	81.89488724145299
2012	91.87457151216852
2013	99.38999011638772
2014	100.88165479446319
2015	103.63628786053933
2016	99.55983805974341
2017	93.01235175477038
2018	98.57470993527654
2019	96.90684638206335
2020	93.37027561219314
2021	97.21018940259151
