Year Percent 1996-01-01 72.788700000000000 1997-01-01 74.986100000000000 1998-01-01 73.882000000000000 1999-01-01 72.152000000000000 2000-01-01 67.007200000000000 2001-01-01 83.454700000000000 2002-01-01 54.722100000000000 2003-01-01 91.581600000000000 2004-01-01 66.727500000000000 2005-01-01 62.858999999999995 2006-01-01 61.515000000000000 2007-01-01 66.580900000000000 2008-01-01 66.706800000000000 2009-01-01 56.670100000000000 2010-01-01 59.508999999999990 2011-01-01 60.110700000000000 2012-01-01 57.169800000000000 2013-01-01 54.181000000000004 2014-01-01 51.248999999999995