Year	current US$
2000	0.91906469
2001	1.91514738
2002	1.82825169
2003	2.76149055
2004	4.69085698
2005	7.14152032
2006	6.63470481
2007	7.58711836
2008	14.29028988
2009	20.66503314
2010	19.29802979
2011	31.00956485
2012	33.30902702
2013	39.13481965
2014	32.89312428
2015	24.57424978
2016	21.11182351
2017	30.81464417
2018	45.78602553
2019	50.12880663
2020	35.69075038
2021	50.90601565