Year	Percent
1991	64.044
1992	63.135
1993	62.901
1994	64.22
1995	65.69
1996	66.826
1997	68.055
1998	68.341
1999	68.841
2000	70.615
2001	69.141
2002	70.879
2003	71.487
2004	71.939
2005	72.569
2006	72.145
2007	71.264
2008	72.498
2009	72.211
2010	70.79
2011	70.237
2012	69.218
2013	67.872
2014	67.775
2015	66.967
2016	67.168
2017	66.834
2018	66.746
2019	66.836
2020	67.017
2021	67.174
2022	67.308