Year Percent of GDP 2004-01-01 4.2923 2005-01-01 4.3183 2006-01-01 4.6238 2007-01-01 5.5438 2008-01-01 5.7280 2009-01-01 9.4068 2010-01-01 10.4363 2011-01-01 12.9718 2012-01-01 15.1477 2013-01-01 17.6112 2014-01-01 18.8035 2015-01-01 20.3033 2016-01-01 23.1379