Year Percent 2001-01-01 2.77 2002-01-01 2.66 2003-01-01 2.41 2004-01-01 2.97 2005-01-01 3.22 2006-01-01 3.19 2007-01-01 3.60 2008-01-01 3.47 2009-01-01 3.44 2010-01-01 3.59 2011-01-01 3.99 2012-01-01 3.71 2013-01-01 3.54 2014-01-01 3.39