Year	current US$
2000	3.28982608
2001	2.79448096
2002	5.18404422
2003	5.69410298
2004	10.61034119
2005	10.8392466
2006	13.19742862
2007	16.42947758
2008	18.83131564
2009	22.24400771
2010	21.49160022
2011	25.51032136
2012	23.22256487
2013	27.21748766
2014	22.46953343
2015	18.87291581
2016	18.43886904
2017	22.70577392
2018	21.23788777
2019	24.79226639
2020	23.60016221
2021	28.74237807