Year	Percent
1991	66.573
1992	66.981
1993	66.037
1994	65.392
1995	65.676
1996	66.344
1997	68.046
1998	69.365
1999	69.84
2000	71.203
2001	71.731
2002	71.91
2003	70.341
2004	69.565
2005	69.121
2006	69.898
2007	70.868
2008	71.425
2009	70.71
2010	68.182
2011	67.094
2012	66.856
2013	65.546
2014	65.353
2015	65.507
2016	65.665
2017	66.093
2018	66.442
2019	66.354
2020	66.035
2021	65.715
2022	65.394