Year current US$ 1992 16467307564.917665 1993 19229749470.656326 1994 23760187524.665024 1995 19376052018.832706 1996 10660838808.249943 1997 7560124762.385896 1998 6396721574.2671995 1999 6439634690.646612 2000 7425449925.600998 2001 8683416697.218466 2002 9543316523.255365 2003 10362910322.848515 2004 11967814473.669462 2005 14154519207.42747 2006 16676107082.671923 2007 19016947275.19317 2008 22161202702.7121 2009 24855857887.178753 2010 27870260718.5304 2011 25694362119.020535 2012 30836220079.287445 2013 36138877868.42852 2014 37904121439.66372 2015 31990154386.37723 2016 31072960597.070553 2017 29262776788.81708 2018 25287123599.37422