Year Percent of GDP 2004-01-01 15.0980 2005-01-01 16.0680 2006-01-01 17.3238 2007-01-01 19.9407 2008-01-01 21.3478 2009-01-01 23.0193 2010-01-01 24.5425 2011-01-01 25.7752 2012-01-01 24.3622 2013-01-01 26.2712 2014-01-01 27.8454 2015-01-01 26.1482 2016-01-01 28.2776