Year Percent of GDP 2004-01-01 5.4607 2005-01-01 7.0015 2006-01-01 9.2146 2007-01-01 12.9280 2008-01-01 15.9695 2009-01-01 16.4024 2010-01-01 16.4388 2011-01-01 16.7518 2012-01-01 17.8022 2013-01-01 18.3195 2014-01-01 19.5286 2015-01-01 20.9308 2016-01-01 20.8392