Year current US$ 2005 11913977402.642366 2006 16520580616.610853 2007 21728749775.01895 2008 28474948949.773964 2009 25145716720.93502 2010 30184026133.643646 2011 33356316266.567547 2012 35197645793.33689 2013 39455617134.6857 2014 39098359294.58508 2015 39433201556.382614 2016 32650144143.221653 2017 40237943893.08136 2018 47653655921.18158