Year Percent 1996-01-01 40.4686 1997-01-01 38.3044 1998-01-01 33.8802 1999-01-01 38.4024 2000-01-01 36.7457 2001-01-01 36.7193 2002-01-01 35.8221 2003-01-01 35.7367 2004-01-01 31.9699 2005-01-01 24.4816 2006-01-01 31.7748 2007-01-01 32.5389 2008-01-01 35.8836 2009-01-01 30.9379 2010-01-01 30.9471 2011-01-01 32.8330 2012-01-01 32.8386 2013-01-01 32.8321 2014-01-01 31.8860