Year current US$ 1995 7000000 1996 6000000 1997 4000000 1998 4000000 1999 11000000 2000 16000000 2001 12000000 2002 10000000 2003 17000000 2004 50000000 2005 58000000 2006 92000000 2007 112000000 2008 304000000 2009 147000000 2010 148000000 2011 247000000 2012 350000000 2013 350000000 2014 390000000 2015 399000000 2016 461000000 2017 292000000 2018 314000000 2019 391000000 2020 89000000