Year	% (national estimate)
1960	40.45626504642898
1970	49.199573105656356
1978	50.26984126984127
1979	50.66434672571971
1980	53.0962290326649
1985	56.45672859084732
1986	56.52959783099865
1988	57.9328009642911
1989	58.761647129546134
1990	62.238203381276804
1991	66.09408773045135
1992	66.88432238653095
1993	67.71421619475713
1994	67.84961897578611
1995	67.69088973699925
1996	72.28258110372138
1997	72.46397107501146
1998	74.08332271626959
1999	74.4559094633347
2000	74.0998868429174
2001	76.00227393118774
2002	77.30472416310356
2003	77.44120021878989
2004	77.81405083786382
2005	79.0178036406248
2006	79.23622621494397
2007	79.10567925350087
2008	81.22871417023363
2009	81.8238609176458
2010	80.67601011459622
2011	81.05318123393316
2012	81.66747207903781
2013	82.41653075253744
2014	83.49158394475616
2015	83.91334222545572
2016	84.34609860535042
2017	84.07095093589709
2018	84.7438677783914
2019	85.51759721920487
2020	85.17993650101518
2021	85.6252407947603
2022	85.47082209680558
2023	85.8485381402506