Year current US$ 1999 4000000 2000 14000000 2001 18000000 2002 2000000 2003 1000000 2004 6000000 2005 11000000 2006 17000000 2007 29000000 2008 33000000 2009 35000000 2010 31000000 2011 34000000 2012 61000000 2013 72000000 2014 78000000 2015 99000000 2016 45000000 2017 46000000 2018 3000000 2019 4000000 2020 5000000