Year	current US$
2000	18.93960762
2001	18.29377747
2002	20.66277122
2003	22.10498047
2004	25.87848282
2005	27.65415382
2006	30.21553993
2007	33.38858795
2008	34.91187286
2009	36.77980042
2010	39.60604477
2011	52.84900284
2012	70.75683594
2013	77.2843399
2014	89.70458221
2015	45.50782776
2016	54.36591339
2017	55.63466263
2018	59.45320129
2019	60.31322479
2020	56.30739212
2021	61.41452789