Year current US$ 1995 255000000 1996 242000000 1997 239000000 1998 346000000 1999 377000000 2000 94000000 2001 14000000 2002 14000000 2003 66000000 2004 84000000 2005 52000000 2006 25000000 2007 99000000 2008 146000000 2009 193000000 2010 409000000 2011 615000000 2012 469000000 2013 524000000 2014 412000000 2015 312000000 2016 235000000 2017 225000000 2018 245000000