Year Percent of GDP 2008-01-01 10.8431 2009-01-01 17.9896 2010-01-01 21.6908 2011-01-01 28.8027 2012-01-01 31.3270 2013-01-01 37.7388 2014-01-01 37.7266 2015-01-01 41.1858 2016-01-01 46.2139 2017-01-01 51.7785