Year current US$ 1995 71000000 1996 50000000 1997 74000000 1998 64000000 1999 49000000 2000 57000000 2001 58000000 2002 72000000 2003 79000000 2004 112000000 2005 138000000 2006 150000000 2007 229000000 2008 293000000 2009 240000000 2010 222000000 2011 253000000 2012 279000000 2013 324000000 2014 328000000 2015 300000000 2016 344000000 2017 442000000 2018 500000000 2019 527000000 2020 354000000