Year current US$ 1995 33000000 1996 38000000 1997 30000000 1998 33000000 1999 39000000 2000 44000000 2001 45000000 2002 48000000 2003 50000000 2004 47000000 2005 45000000 2006 43000000 2007 46000000 2008 44000000 2009 43000000 2010 39000000 2011 37000000 2012 39000000 2013 42000000 2014 51000000 2015 50000000 2016 55000000 2017 53000000 2018 50000000 2019 45400001.5258789 2020 22040000.915527303