Year Percent of GDP 2004-01-01 20.3780 2005-01-01 21.2650 2006-01-01 21.6191 2007-01-01 21.6969 2008-01-01 22.5952 2009-01-01 23.8879 2010-01-01 24.5511 2011-01-01 26.8868 2012-01-01 29.5918 2013-01-01 32.3205 2014-01-01 33.6883 2015-01-01 34.7186 2016-01-01 34.3208