Year	current US$
2000	8.91786003
2001	7.48628187
2002	11.26511002
2003	12.41096115
2004	16.05879211
2005	17.35436821
2006	21.07893753
2007	25.1716423
2008	32.93960953
2009	35.80582047
2010	34.2412796
2011	39.60096741
2012	32.80570221
2013	39.87806702
2014	35.64556885
2015	35.27587891
2016	34.32816696
2017	37.93450165
2018	36.97562408
2019	41.78248596
2020	42.5414238
2021	46.55551147