Year	US Dollars
1990	19061505429.7709
1991	20665413837.493
1992	22941969595.3298
1993	24155186837.1519
1994	26407816115.369
1995	26638819770.5471
1996	28693304914.604
1997	31866945687.3876
1998	33659266804.7902
1999	33727606546.4964
2000	33794665353.6768
2001	33224194745.11869
2002	31405591143.6264
2003	30799235745.4602
2004	33144909208.167
2005	37316358564.4805
2006	40306698709.28441
2007	44093980313.7934
2008	47804248112.4232
2009	50059720219.06919
2010	54370631867.13989
2011	58558594372.8545
2012	62006055895.2299
2013	65756895854.0322
2014	69008843856.41348
2015	70433541533.5553
2016	72427318237.89938
2017	75616207117.07228