Year Percent of GDP 2007-01-01 0.1584 2008-01-01 0.2131 2009-01-01 0.3064 2010-01-01 0.3305 2011-01-01 0.4105 2012-01-01 0.3425 2013-01-01 0.3489 2014-01-01 0.3788 2015-01-01 0.3213 2016-01-01 0.3397