Year	Percent
1990	77.27
1991	76.59
1992	76.93
1993	76.33
1994	77.03
1995	77.01
1996	76.99
1997	76.75
1998	77.72
1999	77.74
2000	77.89
2001	77.05
2002	75.59
2003	75.34
2004	74.92
2005	74.71
2006	74.4
2007	76.31
2008	76.97
2009	76.72
2010	77.54
2011	78.14
2012	78.49
2013	77.92
2014	77.83
2015	77.63
2016	77.26
2017	77.7
2018	78.65
2019	79.1