Year	current US$
1987	900000000
1988	900000000
1989	1000000000
1990	1200000000
1991	1350000000
1993	1174603174.6031744
1996	1175601596.0712094
1997	947718869.1334118
1998	1185453570.5109348
1999	972160956.4226041
2000	1009040993.9587674
2001	1120970501.2406754
2002	1229721019.6190212
2003	1519389829.1441104
2004	1576487447.892543
2005	1857381488.2032666
2006	2004152563.5103927
2007	2355534709.1932454
2008	6109072847.682118
2009	9419903859.649122
2010	11716329122.807016
2011	15181409122.807016
2012	16597507368.421053