Year	Percent
1990	66.78
1991	66.26
1992	65.35
1993	64.99
1994	64.78
1995	64.41
1996	64.22
1997	64.42
1998	64.68
1999	65.07
2000	65.27
2001	65.37
2002	66.33
2003	67.06
2004	67
2005	66.67
2006	66.58
2007	67.06
2008	67.23
2009	66.78
2010	66.62
2011	66.41
2012	66.25
2013	66.22
2014	65.76
2015	65.61
2016	65.49
2017	65.59
2018	65.26
2019	65.57
2020	63.91