Year Percent 1998-01-01 11.289900000000000 1999-01-01 10.561700000000000 2000-01-01 10.007200000000000 2001-01-01 12.069800000000000 2002-01-01 12.143300000000000 2003-01-01 10.489900000000000 2004-01-01 11.800600000000000 2005-01-01 14.326900000000000 2006-01-01 13.551700000000000 2007-01-01 18.516800000000000 2008-01-01 17.530100000000000 2009-01-01 11.883400000000000 2010-01-01 11.097000000000001 2011-01-01 12.266500000000000 2012-01-01 12.005000000000000 2013-01-01 13.751200000000000 2014-01-01 17.427100000000000 2015-01-01 19.896800000000000 2016-01-01 18.317600000000000