Year Percent of GDP 2004-01-01 18.9005 2005-01-01 21.4063 2006-01-01 24.5355 2007-01-01 26.9662 2008-01-01 31.9011 2009-01-01 34.2658 2010-01-01 31.7136 2011-01-01 30.6463 2012-01-01 32.6757 2013-01-01 28.9116 2014-01-01 33.7886 2015-01-01 38.4747 2016-01-01 45.5136 2017-01-01 57.7913