Year	Percent
1991	65.172
1992	65.41
1993	65.447
1994	65.278
1995	65.123
1996	64.881
1997	64.632
1998	64.433
1999	64.252
2000	64.12
2001	64.106
2002	64.079
2003	64.123
2004	64.131
2005	64.1
2006	64.111
2007	64.113
2008	64.102
2009	64.075
2010	64.038
2011	63.961
2012	63.939
2013	63.738
2014	63.556
2015	63.263
2016	63.088
2017	63.09
2018	63.102
2019	63.126
2020	63.165
2021	63.211
2022	63.264