Year	current US$
2000	1.45940718
2001	1.67226265
2002	3.00165304
2003	2.29010001
2004	1.35149864
2005	1.28823678
2006	1.12326945
2007	1.58351943
2008	1.91971067
2009	1.74434018
2010	2.42209186
2011	3.28935648
2012	3.52154587
2013	3.7019954
2014	4.73667072
2015	3.24741869
2016	4.78648133
2017	5.06637218
2018	5.83084353
2019	9.61382026
2020	8.29266804
2021	8.18703654