Year	current US$
1990	12643821568.96257
1991	14665445462.114904
1992	17959367194.004997
1993	21736802664.446297
1994	28019483763.53039
1995	12796345679.012346
1996	6496163615.660856
1997	6838298530.54911
1998	6322175565.946511
1999	7639325295.882872
2000	9679316770.186335
2001	9852990692.987137
2002	10693430511.466354
2003	11777532662.04989
2004	13867634371.477274
2005	16731566717.188839
2006	19063143369.85798
2007	21650528674.09326
2008	26910855807.288002
2009	25130278212.55747
2010	30906749533.221
2011	32726417878.391018
2012	35401331609.59164
2013	40415233436.17665
2014	43228585321.327194
2015	42444490073.85545
2016	31317825274.150734
2017	26842229044.584846
2018	21606160663.03177
