Year	current US$
2000	1.88665592
2001	1.57953665
2002	1.28765342
2003	1.80862259
2004	2.50549688
2005	2.3598251
2006	2.24378715
2007	3.10391021
2008	3.5137228
2009	3.03110124
2010	2.80778992
2011	3.14187176
2012	3.20304387
2013	3.60537469
2014	3.88443007
2015	3.46438589
2016	3.28917712
2017	3.89727783
2018	4.07938416
2019	3.4609526
2020	9.05492204
2021	9.51071087