Year current US$ 1995 5000000 1996 17000000 1997 7000000 1998 6000000 1999 7000000 2000 9000000 2001 5000000 2002 5000000 2003 15000000 2004 21000000 2005 26000000 2006 45000000 2007 101000000 2008 135000000 2009 185000000 2010 167000000 2011 201000000 2012 160000000 2013 197000000 2014 149000000 2015 114000000 2016 128000000 2017 107000000 2018 120000000 2019 129000000 2020 109000000