Year	current US$
2000	20.54365408638909
2001	19.13040680373893
2002	18.367563995392274
2003	25.583010870885545
2004	29.535701611116114
2005	30.94960384361276
2006	34.25984888215972
2007	37.49336602966426
2008	40.23713296126971
2009	38.22182735899478
2010	42.69602177510382
2011	46.05999766700458
2012	46.06947435924883
2013	47.937621274018205
2014	47.70215820699866
2015	43.70916540594921
2016	39.928596772013606
2017	39.304285476183225
2018	37.816031319124484
2019	36.53387985145726
2020	33.91558231911747
2021	38.94617010307871
