Year current US$ 1995 10000000 1996 11000000 1997 11000000 1998 11000000 1999 15000000 2000 15000000 2001 17000000 2002 13000000 2003 13000000 2004 13000000 2005 10000000 2006 10000000 2007 11000000 2008 11000000 2009 11000000 2010 12000000 2011 15000000 2012 22000000 2013 20000000 2014 20000000 2015 17000000 2016 17000000 2017 21000000 2018 28000000 2019 25000000 2020 5000000