Year	Percent
1991	62.168
1992	61.416
1993	61.657
1994	61.267
1995	60.943
1996	61.344
1997	61.962
1998	62.162
1999	62.586
2000	64.463
2001	65.48
2002	65.906
2003	65.332
2004	64.978
2005	64.567
2006	64.198
2007	63.641
2008	63.079
2009	63.779
2010	63.114
2011	62.036
2012	61.868
2013	61.835
2014	61.956
2015	61.853
2016	61.847
2017	61.847
2018	61.84
2019	61.804
2020	61.732
2021	61.636
2022	61.504