Year	current US$
2000	8.58932392
2001	9.5734254
2002	10.03933148
2003	11.10031419
2004	12.12446541
2005	13.67289934
2006	13.27422745
2007	12.91272604
2008	12.82192306
2009	13.23159181
2010	12.73344573
2011	12.50076585
2012	11.79087284
2013	9.63099478
2014	9.00656995
2015	9.45290684
2016	9.50044211
2017	10.11539299
2018	10.17972043
2019	10.99646227
2020	10.60835127
2021	10.43038555