Year Percent of GDP 2004-01-01 12.4470 2005-01-01 13.4065 2006-01-01 15.5414 2007-01-01 16.3652 2008-01-01 17.7343 2009-01-01 18.6657 2010-01-01 20.6532 2011-01-01 20.9272 2012-01-01 20.7949 2013-01-01 20.4767 2014-01-01 20.4596 2015-01-01 20.4811 2016-01-01 20.1714