Year	% (national estimate)
1960	23.891565070403406
1970	26.59690155105642
1980	32.60717400370364
1990	37.22229998359031
1991	39.8677710032338
1992	43.570891306687685
1993	41.83304080655251
1995	43.04233429322328
1996	42.7870599126725
1997	44.301647354600576
1998	44.281227165903935
1999	44.81973942762079
2001	44.6674896337242
2002	46.22818263083442
2003	45.29471302444829
2004	45.566587503786984
2005	45.135586018474
2006	44.98360555110744
2007	44.63234621403043
2008	44.19962071676382
2009	43.825857200521945
2011	41.71683618147952
2012	41.0080353905044
2013	40.659341911864736
2014	39.875871399388885
2015	40.29674277447066
2016	39.863772201821675
2017	40.06033115203575
2018	40.87611522749163
2019	41.56027994309601
2020	37.112293826287335
2021	41.09385635334861
2022	41.43441878455932
2023	40.872372255267685