Year Percent of GDP 2004-01-01 6.0726 2005-01-01 6.7478 2006-01-01 8.2021 2007-01-01 9.3190 2008-01-01 9.2857 2009-01-01 9.1863 2010-01-01 9.7334 2011-01-01 11.5615 2012-01-01 12.8291 2013-01-01 13.8359 2014-01-01 14.8530 2015-01-01 17.1395 2016-01-01 18.0734 2017-01-01 19.8338