Year % (national estimate) 2000 68.94903356342434 2001 71.05895258127538 2002 70.14293563005415 2003 69.77968639760452 2004 69.30021839638783 2005 68.77845351840435 2006 68.64095506397072 2007 68.85666480305272 2008 68.10102040079043 2009 68.01793669520612 2010 66.9646437034243 2011 67.04950462806757 2012 66.91767875593581 2013 66.8449456277592 2014 66.82386940462362 2015 66.63854680333898 2016 66.54977703767763 2017 66.25984131616704 2018 66.18351055962235 2019 66.16048087722001