Year	current US$
2000	14.88457298
2001	16.79668045
2002	17.4725647
2003	21.76790237
2004	25.34852219
2005	25.97800064
2006	27.52271461
2007	27.74564934
2008	29.14166451
2009	30.67226219
2010	30.38452339
2011	32.9503212
2012	34.21852112
2013	34.83580017
2014	33.67948914
2015	28.41767883
2016	29.34768677
2017	29.22344017
2018	34.44770432
2019	29.37922096
2020	30.64243507
2021	35.12914658