Year	US Dollars
1990	13712383156.4238
1991	13944226413.4614
1992	17254758485.556
1993	18685836827.9136
1994	20136816840.535
1995	22038012714.1818
1996	22859491063.53189
1997	24388144440.9442
1998	25687462837.9766
1999	26928155007.3198
2000	29611972564.5122
2001	32075909054.65129
2002	34086360035.0848
2003	36411996715.5927
2004	41071333925.77849
2005	45967589640.20621
2006	51381770988.76129
2007	57258867985.9185
2008	61701079457.63579
2009	65383351595.67802
2010	66119346887.9921
2011	69156949425.67859
2012	72052127928.29399
2013	75474698764.6402
2014	79083797219.88968
2015	81861950185.8606
2016	84880574211.6769
2017	88354217573.53421