Year	current US$
2000	4.60913843
2001	6.20680437
2002	6.51863213
2003	9.36141799
2004	9.26365246
2005	9.94880443
2006	14.21259465
2007	20.39026913
2008	21.06848506
2009	22.12790735
2010	20.45707703
2011	25.36558289
2012	28.1443228
2013	29.43082669
2014	34.51394348
2015	38.47541822
2016	48.95451019
2017	51.83114059
2018	54.47545987
2019	58.03070066
2020	73.52028129
2021	95.44028215