Year current US$ 1995 5527680000 1996 8065690000 1997 21713076000 1998 18625630000 1999 8823340000 2000 14002000000 2001 6066740000 2002 7511460000 2003 7197280000 2004 3541000000 2005 4849090000 2006 9244600000 2007 10458300000 2008 11433350000 2010 16017226000 2011 20922000000 2012 36238430000 2013 18837820000 2014 18452840000 2015 11873970000 2016 21280500000 2017 16739400000 2018 10465260000 2019 21036780000 2020 11050510000