Year Percent of GDP 2004-01-01 26.3724 2005-01-01 27.8322 2006-01-01 29.5238 2007-01-01 29.1811 2008-01-01 28.8319 2009-01-01 30.8548 2010-01-01 32.1752 2011-01-01 31.6252 2012-01-01 32.7972 2013-01-01 33.8261 2014-01-01 34.2538 2015-01-01 34.7326 2016-01-01 34.4779 2017-01-01 37.0694