Year	% (national estimate)
1966	14.04786680541103
1972	9.87189148455162
1976	16.13756613756614
1986	11.046655146877313
1991	12.41707347602954
1996	14.232209737827715
2005	26.130436596798194
2006	25.633197648123023
2007	24.425451635033156
2008	21.902850734816738
2009	22.97759099568107
2010	22.492298167774653
2011	20.808802385240572
2012	22.37970569648822
2013	19.7505595476499
2014	19.263577331759148
2015	21.014725178597462
2016	23.49277456647399
2017	24.87028116468217
2018	24.806124759424883
2019	24.122744708055123
2020	20.38999015473234
2021	19.50393758739972
2022	20.10186405294562