Year	US Dollars
1990	10759824593.2423
1991	11810715701.4423
1992	11345359644.4205
1993	11873634678.683
1994	12955252035.3096
1995	13641370273.7089
1996	14396945627.5323
1997	15474703819.0071
1998	16553485563.0374
1999	15182512492.513
2000	14686315871.8671
2001	15854759512.6146
2002	16704406760.2699
2003	17045050223.654
2004	16766508447.8632
2005	18894569894.5628
2006	18260155780.1174
2007	19523487589.5794
2008	19427839038.746
2009	20177007816.6232
2010	21435382213.9358
2011	23271340614.2618
2012	26027349842.70899
2013	28029283989.74929
2014	31240449913.85881
2015	31732200730.8127
2016	32998954495.565
2017	34452614635.79771