Year Percent of GDP 2004-01-01 18.0196 2005-01-01 18.4017 2006-01-01 17.3914 2007-01-01 18.5466 2008-01-01 21.5708 2009-01-01 22.7499 2010-01-01 23.5510 2011-01-01 22.9208 2012-01-01 21.9642 2013-01-01 21.0813 2014-01-01 20.1047 2015-01-01 20.1837 2016-01-01 18.7773 2017-01-01 7.4352