Year	US Dollars
1990	3557508785.1857
1991	3857468692.75318
1992	4076452179.10882
1993	4319152824.05174
1994	4575284007.62591
1995	4929309478.58283
1996	5208890895.5223
1997	5802859145.4523
1998	6004716751.51855
1999	6638094248.24146
2000	7415575645.11016
2001	7788217838.90634
2002	8182932107.19631
2003	8300211286.32112
2004	8570741506.54006
2005	8691974587.30158
2006	9073729730.59508
2007	9804843818.94723
2008	10452850142.0547
2009	10044816766.1866
2010	10933289438.905
2011	11526803690.5802
2012	11861854799.1017
2013	12652941872.6796
2014	13774972343.24
2015	15312254504.4559
2016	16042918196.3421
2017	17093036751.7795