Year Percent of GDP 2004-01-01 16.8790 2005-01-01 25.4375 2006-01-01 35.5989 2007-01-01 37.5442 2008-01-01 37.2233 2009-01-01 45.7592 2010-01-01 45.2684 2011-01-01 36.8924 2012-01-01 30.0560 2013-01-01 26.4792 2014-01-01 23.7261 2015-01-01 22.0603 2016-01-01 21.1300