Year current US$ 1995 55000000 1996 76000000 1997 55000000 1998 59000000 1999 56000000 2000 61000000 2001 47000000 2002 31000000 2003 33000000 2004 30000000 2005 29000000 2006 29000000 2007 34000000 2008 18000000 2009 26000000 2010 34000000 2011 32000000 2012 28000000 2013 24000000 2014 24000000 2015 26000000 2016 52000000 2017 83000000 2018 96000000 2019 96000000 2020 41000000