Year	current US$
2000	0.5369424018062878
2001	0.5333263607274008
2002	0.613227180429224
2003	0.8056379264273309
2004	1.3980009353142606
2005	1.440966971348991
2006	1.5018698410863422
2007	1.8827650589001974
2008	2.100092740989363
2009	2.145963905927596
2010	2.391500707769498
2011	2.7517721173560554
2012	2.6769310432995086
2013	2.932518421957919
2014	2.9086925525883465
2015	2.4478782800528536
2016	2.3073415782496003
2017	2.3191494727380273
2018	2.315815951932396
2019	2.4710495433855098
2020	2.3393881872795443
2021	3.799518201497731