Year	% (national estimate)
1965	52.71
1975	51.43
1992	47.13
1997	31.1
2000	30.675
2001	34.663
2002	31.837
2003	29.228
2004	29.504
2005	27.869
2006	28.867
2007	28.893
2008	30.132
2009	29.537
2010	31.16
2011	29.454
2012	30.433
2013	29.644
2014	27.214
2015	25.96
2016	23.887
2017	26.299
2018	23.688
2019	23.913
2020	21.887
2021	19.978
2022	22.24
2023	21.358