Year Percent of GDP 2004-01-01 33.8555 2005-01-01 36.7618 2006-01-01 38.8469 2007-01-01 40.4226 2008-01-01 42.8208 2009-01-01 44.4256 2010-01-01 45.3225 2011-01-01 46.3298 2012-01-01 47.2880 2013-01-01 47.7394 2014-01-01 47.8220 2015-01-01 48.7882 2016-01-01 49.7338 2017-01-01 50.8262