Year Percent 2001-01-01 2.7486200000000003 2002-01-01 1.8123000000000000 2003-01-01 1.6928800000000000 2004-01-01 14.6702000000000000 2005-01-01 10.4941000000000000 2006-01-01 11.8415000000000000 2007-01-01 17.5319000000000000 2008-01-01 15.3835000000000000 2009-01-01 20.6130000000000030 2010-01-01 24.5575000000000000 2011-01-01 25.3860000000000000 2012-01-01 32.2088000000000000 2013-01-01 31.7612000000000000 2014-01-01 28.7698000000000000 2015-01-01 29.1311000000000000 2016-01-01 28.8222000000000000