Year Percent of GDP 2004-01-01 18.2072 2005-01-01 18.8633 2006-01-01 19.5642 2007-01-01 22.0298 2008-01-01 24.6797 2009-01-01 24.0667 2010-01-01 21.8038 2011-01-01 21.4494 2012-01-01 23.4051 2013-01-01 25.3034 2014-01-01 24.7025 2015-01-01 24.8184 2016-01-01 28.2314