Year current US$ 1995 36000000 1996 104000000 1997 84000000 1998 85000000 1999 60000000 2000 57000000 2001 73000000 2002 62000000 2003 182000000 2004 158000000 2005 175000000 2006 181000000 2007 226000000 2008 156000000 2009 270000000 2010 159000000 2011 409000000 2012 349000000 2013 576000000 2014 595000000 2015 450000000 2016 505000000 2017 525000000 2018 581000000 2019 653000000 2020 437000000