Year current US$ 1995 18000000 1996 18000000 1997 18000000 1998 15000000 1999 16000000 2000 13000000 2001 19000000 2002 24000000 2003 18000000 2004 24000000 2005 26000000 2006 12000000 2007 14000000 2008 15000000 2009 13000000 2010 14000000 2011 18000000 2012 19000000 2013 14000000 2014 10000000 2015 11000000 2016 10000000 2017 10000000 2018 11000000 2019 9000000 2020 2000000