Year	Percent
1991	73.767
1992	73.901
1993	74.207
1994	73.915
1995	73.491
1996	72.856
1997	70.313
1998	65.344
1999	69.517
2000	67.965
2001	75.972
2002	75.652
2003	75.172
2004	73.845
2005	74.691
2006	75.503
2007	76.631
2008	77.202
2009	77.488
2010	77.456
2011	76.732
2012	76.137
2013	75.382
2014	74.984
2015	74.351
2016	73.615
2017	73.598
2018	73.533
2019	73.441
2020	73.337
2021	73.22
2022	73.083