Year	US Dollars
1990	3111016518.6849
1991	3400846593.50555
1992	2718062427.89825
1993	2987698790.28496
1994	2778709738.48868
1995	2801557103.77647
1996	2981555491.6914
1997	2896245288.23618
1998	2883224654.17568
1999	2916834558.06823
2000	3199419807.21008
2001	3084249416.97516
2002	3962740820.47133
2003	4438488016.92247
2004	4848126856.13922
2005	5224946404.77404
2006	5631412622.45539
2007	6685882419.88467
2008	7382685467.29588
2009	7733784585.08598
2010	7677386079.46074
2011	8124629823.32659
2012	9976219409.79926
2013	11791530641.4532
2014	12319659466.4518
2015	9992331550.0772
2016	9701082579.03506
2017	11195694798.513