Year current US$ 1995 4000000 1996 5000000 1997 4000000 1998 1000000 1999 4000000 2000 4000000 2001 15000000 2002 12000000 2003 12000000 2004 13000000 2005 19000000 2006 19000000 2007 14000000 2008 12000000 2009 13000000 2010 14000000 2011 5000000 2012 4000000 2013 4000000 2014 4000000 2015 4000000 2016 4000000 2017 4000000 2018 6000000 2019 7000000 2020 5000000