Year % (national estimate) 1960 68.49444130393819 1989 93.876731580004 1990 89.05080740448994 1991 88.84454200758333 1992 89.77850030481609 1993 75.16971816498663 1995 67.5103734439834 1996 65.3486394557823 1997 58.6021505376344 1998 59.675236806495256 1999 60.27777777777777 2000 65.33923303834808 2002 69.23293059848271 2003 63.36287313432835 2004 64.41558441558442 2005 65.311004784689 2006 65.71222329162656 2007 60.08802067995157 2008 74.2970123022847 2009 71.29300485301846 2010 73.25392359157131 2011 77.71920992626374 2012 74.82038634170254 2013 71.2640882186005 2014 69.43672644607224 2015 73.32533088063354 2016 76.66209362909068 2017 74.50995129577296 2018 76.11829615567157 2019 77.83371606901018