Year current US$ 1995 52000000 1996 44000000 1997 38000000 1998 36000000 1999 45000000 2000 42000000 2001 26000000 2002 17000000 2003 18000000 2004 52000000 2005 96000000 2006 109000000 2007 73000000 2008 83000000 2009 70000000 2010 69000000 2011 69000000 2012 79000000 2013 92000000 2014 103000000 2015 99000000 2016 74000000 2017 61000000 2018 73000000 2019 64000000 2020 19000000