Year	current US$
2000	0.83524115
2001	0.92988251
2002	2.31915407
2003	1.7213985
2004	2.69873602
2005	3.49706869
2006	5.27296392
2007	5.43011554
2008	7.03792479
2009	8.37767051
2010	8.80869389
2011	10.58584274
2012	11.77827469
2013	12.99918432
2014	16.2654607
2015	12.28990624
2016	8.55609562
2017	8.36856443
2018	11.18587426
2019	5.1415785
2020	1.79810888
2021	11.90291102