Year	constant 2015 US$
1989	20000
1990	10000
1991	10000
1992	21040000
1993	94360000
1994	562880000
1995	1117090000
1996	1059240000
1997	1150820000
1998	1227890000
1999	1728570000
2000	1090500000
2001	946350000
2002	779610000
2003	644300000
2004	748100000
2005	575010000
2006	556300000
2007	562610000
2008	401670000
2009	381670000
2010	471600000
2011	535490000
2012	511560000
2013	453460000
2014	548330000
2015	355310000
2016	445410000
2017	433200000