Year	% (national estimate)
1988	54.82
1989	54.96
1990	52.077
1991	52.326
1992	51.241
1993	47.498
1994	49.974
1995	50.005
1996	50.174
1997	48.969
1998	49.173
1999	48.668
2000	46.704
2001	45.646
2002	44.442
2003	43.235
2004	41.289
2005	41.495
2006	41.528
2007	41.484
2008	41.745
2009	41.166
2010	43.002
2011	44.986
2012	45.359
2013	45.898
2014	45.507
2015	46.014
2016	46.328
2017	47.065
2018	47.382
2019	45.681
2020	42.846
2021	45.204
2022	47.503
2023	48.308
