Year	% (national estimate)
1960	42.25
1976	35.47
1988	43.71
1989	49.04
1990	50
1991	53.32
1992	45.06
1995	49.12
1999	38.585
2000	39.037
2001	42.137
2002	38.828
2003	40.18
2004	38.296
2005	39.413
2006	38.555
2007	39.825
2008	40.592
2009	38.869
2010	40.297
2011	36.612
2012	35.614
2013	36.357
2014	39.587
2015	38.98
2016	38.494
2017	40.068
2018	41.881
2019	40.061
2020	36.742
2021	39.676
2022	41.068
2023	42.684