Year Percent 2005-01-01 44.5997979257005 2006-01-01 45.6164905682295 2007-01-01 46.6905392190913 2008-01-01 47.4275735613965 2009-01-01 47.5152123084867 2010-01-01 47.9667457690203 2011-01-01 48.9095971554341 2012-01-01 49.1991174834054 2013-01-01 49.5969687216562