Year % (national estimate) 1966 8.72 1975 28.59 1980 24.33 1984 31.12 1989 26.24 1997 27.27 2005 20.769 2006 19.82 2007 20.6 2008 20.684 2009 19.233 2010 20.161 2011 20.587 2012 22.788 2013 21.351 2014 18.45 2015 18.226 2016 20.677 2017 19.263 2019 25.963 2022 16.9 2023 14.838