Year Percent of GDP 1999 -1.526 2000 0.548 2001 1.42 2002 7.649 2003 13.473 2004 15.1 2005 13.254 2006 14.991 2007 13.795 2008 13.446 2009 19.82 2010 25.519 2011 26.759 2012 28.323 2013 29.11 2014 29.418 2015 28.056 2016 24.912 2017 21.543