Year current US$ 1995 73000000 1996 77000000 1997 75000000 1998 73000000 1999 69000000 2000 86000000 2001 90000000 2002 109000000 2003 118000000 2004 135000000 2005 170000000 2006 224000000 2007 290000000 2008 359000000 2009 307000000 2010 298000000 2011 349000000 2012 396000000 2013 428000000 2014 442000000 2015 370000000 2016 334000000 2017 380000000 2018 438000000 2019 479000000 2020 303000000