Year	current US$
2000	0.40902325
2001	0.99024582
2002	1.12214363
2003	1.75502485
2004	3.16590521
2005	1.66104972
2006	3.59346012
2007	4.91632728
2008	5.11003243
2009	8.96433173
2010	4.41200957
2011	4.64079936
2012	2.97600493
2013	6.00117871
2014	5.13304497
2015	18.87421127
2016	16.67399629
2017	16.93358079
2018	7.66833632
2019	26.56045753
2020	53.21788878
2021	32.06004473