Year Percent 1996-01-01 22.810100000000000 1997-01-01 15.575600000000000 1998-01-01 16.378200000000000 1999-01-01 18.737700000000000 2000-01-01 19.695999999999998 2001-01-01 28.301200000000000 2002-01-01 11.864300000000000 2003-01-01 14.081700000000000 2004-01-01 31.167800000000000 2005-01-01 13.859200000000000 2006-01-01 18.716300000000000 2007-01-01 22.929400000000000 2008-01-01 14.926300000000000 2009-01-01 15.053300000000000 2010-01-01 7.101990000000000 2011-01-01 11.069400000000000 2012-01-01 10.343900000000000 2013-01-01 17.296800000000000 2014-01-01 12.095800000000000 2015-01-01 14.439700000000000 2016-01-01 14.112200000000000