Year current US$ 2006 8333164440.81801 2007 9655788162.37815 2008 10745400711.98 2009 10093674161.8072 2010 9064406121.79263 2011 8594790051.88045 2012 7633055141.52202 2013 7481230639.09747 2014 7430691286.67725 2015 6138353300.15198 2016 6756997762.92378 2017 6122858369.12136 2018 6726724756.11911 2019 6368166038.07197 2020 5885864650.16207 2021 6697638208.87311