Year	current US$
1998	563.8884747806702
1999	628.095348014092
2000	449.63617755258736
2001	333.960004317175
2002	292.1021742323376
2003	298.9154754405567
2004	365.39294449513517
2005	444.04611643053846
2006	482.3457275175899
2007	669.4146984678874
2008	826.8650438767489
2009	980.8922742129224
2010	1432.6374280190357
2011	1637.7989720594728
2012	1814.724146056723
2013	1968.6793844945541
2014	2200.257553423481
2015	2373.9940848099804
2016	2317.039118855278
2017	1622.3836940246877
2018	1280.3552460832655
2019	1446.206282051944
2020	1395.924210541697
2021	1429.8129240876183