Year Percent of GDP 2004-01-01 16.6414 2005-01-01 19.5596 2006-01-01 21.7325 2007-01-01 25.1452 2008-01-01 26.2573 2009-01-01 25.4530 2010-01-01 24.9512 2011-01-01 25.5812 2012-01-01 25.9407 2013-01-01 26.4188 2014-01-01 27.2050 2015-01-01 27.2915 2016-01-01 27.5837 2017-01-01 29.4192