Year	Percent
1992	65.1716
1993	64.9906
1994	64.97414
1995	64.98119
1996	64.97414
1997	64.96709
1998	64.25482
1999	64.24777
2000	62.68393
2001	62.68481
2002	62.04478
2003	61.63436
2004	61.22248
2005	60.80776
2006	60.39234
2007	59.95862
2008	59.54579
2009	59.13361
2010	58.72556
2011	58.32142
2012	57.9073
2013	57.50489
2014	58.61093
2015	57.98457
2016	57.98053
2017	57.95255
2018	57.92341
2019	58.00706
2020	58.28322
2021	58.3012