Year	current US$
2000	1.80514472
2001	2.33765595
2002	2.66172601
2003	2.65772644
2004	2.5854963
2005	2.85534024
2006	2.94234756
2007	2.56634329
2008	2.93392211
2009	3.84030391
2010	5.27576968
2011	5.12366564
2012	5.41223506
2013	5.69553355
2014	9.39346636
2015	7.47398503
2016	5.34743461
2017	4.12245512
2018	3.9944413
2019	6.29584001
2020	6.73079768
2021	9.76845378
