Year Percent of GDP 2004-01-01 7.8902 2005-01-01 12.7910 2006-01-01 18.8643 2007-01-01 24.7201 2008-01-01 26.4601 2009-01-01 30.6556 2010-01-01 27.7407 2011-01-01 23.6059 2012-01-01 21.5848 2013-01-01 20.4550 2014-01-01 19.5900 2015-01-01 20.0924 2016-01-01 20.7887 2017-01-01 22.2970