Year	current US$
2000	2.75381188
2001	3.21580219
2002	1.06968092
2003	0.96398639
2004	0.6713376
2005	0.54783476
2006	0.32110067
2007	0.40120787
2008	0.7163503
2009	1.50364238
2010	1.37813799
2011	0.95942122
2012	0.49274428
2013	0.31876697
2014	0.19835627
2015	0.05574278
2016	0.24695574
2017	0.45709612
2018	0.05604324
2019	0.00953929
2020	1.29420147
2021	0.44561671