Year	current US$
2000	157.24229955
2001	160.85191231
2002	174.86299206
2003	221.76373315
2004	250.62015643
2005	263.4417065
2006	356.7157311
2007	410.89450372
2008	482.1667737
2009	481.65994345
2010	470.03186625
2011	505.02142435
2012	470.03125285
2013	489.24557756
2014	496.24430034
2015	409.17840627
2016	409.66573815
2017	427.52753114
2018	443.35718758
2019	425.80686234
2020	420.30360571
2021	480.22670019