Year	current US$
2002	0.15160967
2003	1.29700564
2004	1.18617905
2005	1.33553256
2006	1.35533866
2007	1.84962338
2008	2.44655618
2009	2.34359473
2010	2.55007354
2011	2.93559049
2012	2.28442458
2013	2.83484999
2014	2.98555852
2015	3.10637149
2016	3.12218743
2017	3.40957279
2018	2.77333833
2019	2.48787785
2020	6.1311352
2021	2.6857651