Year % (national estimate) 1981 51.73 1985 58.63 1991 35.67 1994 41.5 1996 31.941 1998 37.37 2000 36.34 2001 34.29 2006 37.344 2009 35.621 2010 34.69 2013 42.74 2019 31.595 2020 32.405 2021 35.942 2022 35.91 2023 38.721