Year	current US$
2000	176.29107348
2001	206.39867881
2002	222.38088069
2003	242.17532563
2004	253.34228976
2005	280.54202376
2006	295.04877432
2007	314.89508736
2008	311.92471621
2009	264.95863567
2010	268.45313994
2011	269.36262747
2012	275.79664122
2013	291.92890156
2014	294.74695711
2015	266.7975334
2016	240.12960445
2017	254.68829643
2018	267.29619444
2019	280.95450904
2020	253.62606822
2021	304.04696362