Year	current US$
2000	166.11361998
2001	153.42164093
2002	186.96139106
2003	193.07486198
2004	242.01502649
2005	269.38166287
2006	308.37280893
2007	352.84614451
2008	383.92433664
2009	398.69299705
2010	418.84356314
2011	428.04505174
2012	448.69045841
2013	460.7939731
2014	491.68495922
2015	503.07843561
2016	518.53217177
2017	505.20806235
2018	544.33884462
2019	578.37333056
2020	568.96269589
2021	592.06878567