Year	% (national estimate)
1966	6.6115702479338845
1975	23.3133971291866
1980	24.592854437571017
1984	27.682186234817813
1989	26.96032904338596
1994	31.019522776572668
1997	32.226004084411166
2003	35.860655737704924
2005	34.802664544463106
2006	36.249609891661336
2007	36.17599692685016
2008	36.37928244656596
2009	36.09513966724406
2010	35.75570937243672
2011	35.478441943719425
2012	36.65310882302747
2013	36.517840569984436
2014	33.33333333333333
2015	37.85092246630708
2016	38.83560343946627
2017	38.80059179398538
2019	39.7377938517179
2022	41.921015038171454
2023	41.10766954833341