Year	current US$
1981	165973487.8403471
1982	164026874.16446713
1983	137837667.05176297
1984	115801514.39178702
1985	119974849.94022438
1986	250935431.46475938
1990	794244257.7867938
1998	756301054.1467414
1999	815790963.0339549
2000	784548399.6808137
2001	755820538.1834949
2002	916238174.4647496
2003	1446529830.7856314
2004	1568230207.6076016
2005	1862027612.2388175
2006	2364056149.0995045
2007	3313898830.0949335
2008	3745190394.305367
2009	2963025958.4679613
2010	3974593706.9027405
2011	4312935170.8265085
2012	3952243492.9793754
2013	3993969029.859147
2014	3786412668.6827126
2015	3034125408.0746655
2016	2550701432.4585934
2017	2549627494.5240164