Year current US$ 1995 10000000 1996 13000000 1997 13000000 1998 16000000 1999 18000000 2000 22000000 2001 20000000 2002 24000000 2003 26000000 2004 31000000 2005 37000000 2006 41000000 2007 47000000 2008 70000000 2009 72000000 2010 77000000 2011 89000000 2012 79000000 2013 79000000 2014 84000000 2015 308000000 2016 321000000 2017 371000000 2018 345000000 2019 336000000 2020 104000000