Year	% (national estimate)
1986	19.527
1987	22.358
1988	23.344
1989	24.879
1990	25.847
1991	25.204
1992	23.795
1993	20.424
1994	19.782
1995	19.973
1996	19.251
1997	20.133
1998	21.13
1999	23.788
2000	26.793
2001	27.395
2002	27.836
2003	28.827
2004	29.288
2005	32.982
2006	34.651
2007	34.094
2008	32.563
2009	26.699
2010	24.395
2011	21.939
2012	18.335
2013	16.319
2014	16.036
2015	17.269
2016	17.221
2017	19.776
2018	20.582
2019	20.157
2020	16.563
2021	19.179
2022	21.46
2023	22.126