Year Percent 1996-01-01 41.7877 1997-01-01 42.7218 1998-01-01 52.3810 1999-01-01 57.6124 2000-01-01 72.1981 2001-01-01 65.6698 2002-01-01 61.0483 2003-01-01 60.4579 2004-01-01 58.2775 2005-01-01 52.0942 2006-01-01 47.4726 2007-01-01 56.6324 2008-01-01 56.1881 2009-01-01 53.8432 2010-01-01 46.1223 2011-01-01 53.5484 2012-01-01 35.5493 2013-01-01 34.6413 2014-01-01 35.3158