Year	current US$
2000	167.80309751
2001	168.21938673
2002	192.90327943
2003	211.7759501
2004	290.34283561
2005	325.60355
2006	325.13831333
2007	370.40235464
2008	369.90712771
2009	299.33042947
2010	341.95706465
2011	265.43974781
2012	298.75459712
2013	309.21271517
2014	309.89300967
2015	311.17899292
2016	310.29625056
2017	335.62245956
2018	329.10056257
2019	323.23345799
2020	400.71995326
2021	409.53506436