Year	% (national estimate)
1964	23.224699828473412
1973	30.273833671399597
1980	28.556858745537987
1985	46.27215467994727
1986	61.04868913857678
1987	62.25045372050816
1989	58.69097354095455
1993	63.182072829131656
1996	67.2072072072072
2000	77.19345680681357
2001	64.76820551275384
2002	64.3097643097643
2003	65.72087292777242
2004	65.37594956969257
2005	63.82801319146289
2007	63.75510307901665
2008	64.1270405443144
2009	66.93582344636268
2010	67.76288019863439
2011	68.13877006008752
2012	69.43187717866944
2013	69.32163347958151
2014	69.17375272782
2015	69.67117258723671
2016	69.58545214755823
2017	69.49619371867946
2018	68.48191164782197
2019	68.26592222294359
2020	67.02666614303106
2021	66.6495031151846
2022	67.0607686957891
2023	68.05591881571375