Year	current US$
1990	3796272748.004896
1991	5155121523.730225
1992	6672077801.831807
1993	9011870308.076603
1994	11388867002.497917
1995	5094369669.135802
1996	2218511373.390558
1997	2287499651.1987624
1998	2537613402.714306
1999	2708372477.275091
2000	3169928380.745342
2001	3562163330.96212
2002	3906548440.5471964
2003	4280063371.6781654
2004	4962266867.914317
2005	5585561594.301243
2006	6354814546.652893
2007	7204662561.542084
2008	8942911610.86963
2009	8342062058.628748
2010	10250391374.834919
2011	10845793630.963516
2012	13898991955.94986
2013	15891512749.313602
2014	16614979463.446415
2015	17796084732.21783
2016	14095156887.29912
2017	11572998243.719873
2018	9033938045.9594