Year	current US$
1995	43000000
1996	28000000
1997	33000000
1998	29000000
1999	35000000
2000	55000000
2001	74000000
2002	91000000
2003	119000000
2004	176000000
2005	667000000
2006	1414000000
2007	1477000000
2008	1268000000
2009	868000000
2010	1127000000
2011	937000000
2012	699000000
2013	460000000
2014	439000000
2015	195000000
2016	203000000
2017	29000000
2018	13000000