Year	US Dollars
1990	21601636465.5358
1991	22756430939.3848
1992	23485708830.71749
1993	23914392391.7766
1994	25481661080.9334
1995	27969588971.5174
1996	31164073110.9008
1997	33385121847.4356
1998	35958022503.7468
1999	36929421473.5848
2000	35340919846.02081
2001	35354124610.28941
2002	34887113106.3257
2003	34105092595.6703
2004	37198239006.269
2005	42123506238.7944
2006	43998021300.6603
2007	45972598726.3584
2008	48199887689.7841
2009	50070132013.2808
2010	51803144648.9724
2011	50433570908.0155
2012	57278462371.2207
2013	62511110326.9041
2014	70636409205.5388
2015	77343489686.31889
2016	85006935427.35921
2017	92838436305.6521