Year Percent 1994-01-01 40.164500000000000 1995-01-01 41.734800000000000 1996-01-01 43.642400000000000 1997-01-01 33.540500000000000 1998-01-01 33.333800000000000 1999-01-01 33.591500000000000 2000-01-01 31.450700000000000 2001-01-01 30.522700000000000 2002-01-01 28.985200000000000 2003-01-01 29.238500000000000 2004-01-01 29.172900000000000 2005-01-01 27.346800000000000 2006-01-01 27.721100000000000 2007-01-01 26.788500000000000 2008-01-01 25.336200000000000 2009-01-01 24.923700000000000 2010-01-01 24.273000000000003 2011-01-01 25.278600000000000 2012-01-01 24.747900000000000 2013-01-01 26.001400000000000 2014-01-01 26.252600000000000 2015-01-01 24.017900000000000 2016-01-01 24.634300000000000