Year Percent 2003-01-01 78.6242120780224 2004-01-01 77.7736096206203 2005-01-01 79.2810422056495 2006-01-01 80.1207527280474 2007-01-01 80.7832775742030 2008-01-01 79.4892751271616 2009-01-01 74.5198326976008 2010-01-01 74.2934949773133 2011-01-01 74.1736232669225 2012-01-01 75.0884578150249 2013-01-01 76.3397812526724