Year	% (national estimate)
1978	40.97
1979	41.18
1981	45.21
1985	44.8
1986	44.93
1987	44.79
1988	45.25
1989	45.38
1990	44.73
1991	42.74
1992	46.593
1993	43.466
1994	41.922
1995	40.002
1996	36.38
1997	36.042
1998	37.25
1999	38.888
2000	39.262
2001	39.123
2002	39.288
2003	40.088
2004	39.772
2005	39.883
2006	39.966
2007	39.653
2008	39.312
2009	38.66
2010	39.107
2011	39.136
2012	40.198
2013	40.554
2014	42.782
2015	44.023
2016	45.581
2017	46.159
2018	46.75
2019	47.045
2020	46.325
2021	50.577
2022	51.811
2023	52.212