Year % (national estimate) 1971 17.65338664667424 1981 29.28093128382787 1991 31.571249174740707 1994 22.453898089156787 2000 25.645409621178576 2001 29.950000000000003 2005 25.958076931697438 2010 20.77639682474959 2012 17.431683898926185 2018 11.354469005974577 2019 13.386082608769689 2020 12.534250954690226 2021 13.962366112874431 2022 13.73375556702114 2023 17.462862633287678