Year % (national estimate) 1979 37.61 1989 34.23 1995 46.18 1998 51.81 1999 38.54 2001 36.39 2002 36.24 2003 35.62 2014 32.5 2015 31.77 2016 31.03 2017 29.99 2018 29.969 2019 31.669 2020 27.907 2021 28.089