Year	US Dollars
1990	538636336146.24402
1991	546346367866.2381
1992	562155404800.104
1993	591957405095.22412
1994	630524141038.93799
1995	661850079058.96704
1996	685658408523.979
1997	728903659462.26697
1998	763330790723.54797
1999	815017509090.45093
2000	874383431862.04211
2001	908341201463.47192
2002	942989409704.28662
2003	994451398771.05505
2004	1056629674010.84021
2005	1143631081272.60034
2006	1218242050349.44995
2007	1278020370057.42017
2008	1319337486531.80981
2009	1281970209327.04004
2010	1334171352202.12988
2011	1400440679278.3999
2012	1438515129675.47021
2013	1526600490196.08032
2014	1591364464651.75024
2015	1575248164727.81006
2016	1603884245584.87012
2017	1691095434431.13965
