Year Percent of GDP 2004-01-01 23.3242 2005-01-01 20.8869 2006-01-01 22.0646 2007-01-01 21.7643 2008-01-01 29.1131 2009-01-01 20.3653 2010-01-01 21.2672 2011-01-01 22.1197 2012-01-01 23.5329 2013-01-01 26.8086 2014-01-01 26.1470 2015-01-01 29.2955 2016-01-01 27.6148 2017-01-01 27.6066