Year	current US$
2000	1.07863425
2001	3.25356862
2002	2.72142133
2003	5.2206497
2004	5.23603583
2005	5.75259939
2006	6.88250817
2007	8.96770648
2008	4.81604321
2009	7.1191619
2010	4.78923406
2011	3.73397759
2012	4.9852749
2013	3.43027658
2014	1.49238083
2015	1.95767853
2016	1.82667128
2017	1.63780917
2018	1.4785833
2019	2.44393875
2020	2.683289
2021	2.52997887