Year current US$ 1995 19000000 1996 15000000 1997 7000000 1998 11000000 1999 10000000 2000 6000000 2001 10000000 2002 5000000 2003 9000000 2004 14000000 2005 24000000 2006 55000000 2007 117000000 2008 113000000 2009 82000000 2010 74000000 2011 89000000 2012 140000000 2013 155000000 2014 155000000 2015 140000000 2016 99000000 2017 145000000 2018 169000000 2019 137000000 2020 27000000