Year	current US$
2000	1.728384782488914
2001	1.0585083982266523
2002	1.2263990773007953
2003	1.4801179761886059
2004	2.1304773151424943
2005	2.5658549554392915
2006	3.414696529893131
2007	3.997241033824496
2008	4.806968836289392
2009	4.926768840213509
2010	5.630565412722541
2011	6.898392472065626
2012	6.901654277849442
2013	8.628726582459064
2014	9.278581578803376
2015	7.934040321688685
2016	7.753473627840144
2017	7.932221817450928
2018	7.534561169286219
2019	8.438092748146639
2020	8.37331516576863
2021	9.121693149203786