Year	US Dollars
1990	128141872437.939
1991	47587174077.7071
1992	64811096109.03209
1993	87419173031.14508
1994	92724936432.3645
1995	96638819401.88301
1996	109237303751.58003
1997	132991561000.92398
1998	181245740676.49802
1999	215458953157.85803
2000	226012366918.08499
2001	236295376305.80301
2002	221114484820.5939
2003	153675057334.03598
2004	243495337533.65402
2005	265895499802.19601
2006	301588711912.63898
2007	314839183964.96301
2008	359941628463.36102
2009	365766856162.89093
2010	387717490234.39001
2011	420294877136.849
2012	490591644546.84003
2013	531533682467.15009
2014	544627295386.672
2015	575486314401.99097
2016	646329957624.4751
2017	650876374623.87598