Year	US Dollars
1990	19515029595.6379
1991	19996002377.37329
1992	22448871775.9771
1993	24356952474.9078
1994	26744914202.7701
1995	29190915891.4186
1996	31670281787.20359
1997	34035713363.0238
1998	36426378258.3671
1999	41029437130.5789
2000	47716896625.59969
2001	54306327175.74451
2002	61788569660.1152
2003	71752392635.24139
2004	83735295669.96729
2005	98140849210.38129
2006	114407144130.29102
2007	131552844878.483
2008	147881182310.54102
2009	164736692579.97595
2010	182820540037.75
2011	197034773408.76199
2012	206862942836.98798
2013	229322853490.04001
2014	248364503884.91202
2015	270230503637.38501
2016	292589523854.64093
2017	311247943759.03693