Year	US Dollars
1990	28885538538.2137
1991	30711813694.83369
1992	33710048305.6096
1993	34664498798.47481
1994	36777633557.6798
1995	38805473301.2702
1996	42095994918.0745
1997	45590118235.3185
1998	48485878342.2097
1999	52228400218.61569
2000	55655541950.0544
2001	59261356555.2529
2002	60980830739.96929
2003	65328106800.73609
2004	71164860273.4473
2005	75167405561.61548
2006	81945919572.27699
2007	89034230314.58548
2008	94186782259.02969
2009	98856159133.01822
2010	103689920157.77699
2011	103777406437.032
2012	110476647608.062
2013	115212881723.666
2014	121904014940.319
2015	125254069897.33398
2016	127261464533.214
2017	132558909740.62199