Year	Percent
1991	81.258
1992	78.257
1993	82.577
1994	82.747
1995	82.219
1996	83.595
1997	81.302
1998	88.825
1999	84.342
2000	73.519
2001	69.053
2002	74.16
2003	73.945
2004	73.738
2005	75.539
2006	74.013
2007	74.46
2008	77.219
2009	75.228
2010	76.29
2011	75.32
2012	78.242
2013	73.663
2014	73.057
2015	74.537
2016	76.421
2017	76.458
2018	76.43
2019	76.401
2020	76.373
2021	76.344
2022	76.317