Year	US Dollars
1990	12446712432.3946
1991	11947871795.0984
1992	8676362870.00875
1993	7353549240.77526
1994	5807213241.13941
1995	5127280806.07743
1996	4196475481.4983
1997	4563267139.0141
1998	4860000144.39685
1999	5105840071.23462
2000	5569314868.81951
2001	6245047061.34345
2002	7028585898.17297
2003	7860800935.0218
2004	9109278429.17529
2005	10062746492.6626
2006	11076715542.0614
2007	12420217673.3986
2008	13843853803.2611
2009	14419672247.789
2010	19480738652.0818
2011	22041323704.1279
2012	24161396942.9749
2013	27285893934.1001
2014	27737910420.76099
2015	28712309304.9285
2016	30566762104.3882
2017	32734568321.20029