Year	Percent
1990	84.43
1991	84.34
1992	84.27
1993	84.19
1994	84.1
1995	84
1996	84.12
1997	84.28
1998	84.49
1999	84.75
2000	85.07
2001	85.47
2002	85.91
2003	86.37
2004	86.8
2005	87.18
2006	87.35
2007	87.5
2008	87.63
2009	87.76
2010	86.88
2011	85.78
2012	84.93
2013	84.91
2014	82.28
2015	85.9
2016	85.94
2017	85.96
2018	85.97
2019	85.98