Year	current US$
2000	92.61007188
2001	94.91209707
2002	100.87900246
2003	100.59474574
2004	111.69610828
2005	115.91497588
2006	123.81346444
2007	141.68135713
2008	148.2927544
2009	163.93663742
2010	191.23448817
2011	227.47765901
2012	252.49137378
2013	260.34497188
2014	292.57738404
2015	324.68020148
2016	345.7528702
2017	359.91273664
2018	438.47608537
2019	504.14881217
2020	537.78560363
2021	528.33483547