Year	current US$
1998	160000000
1999	164000000
2000	127000000
2001	136000000
2002	135000000
2003	134000000
2004	183000000
2005	224000000
2006	225000000
2007	247000000
2008	246000000
2009	277000000
2010	252000000
2011	258000000
2012	148000000
2013	161000000
2014	158000000
2015	79000000
2016	56000000