Year	Percent
1991	95.304
1992	94.637
1993	95.05
1994	94.799
1995	94.641
1996	91.948
1997	91.751
1998	90.998
1999	90.408
2000	93.467
2001	93.278
2002	92.826
2003	92.43
2004	92.731
2005	91.998
2006	91.45
2007	91.001
2008	90.372
2009	90.362
2010	89.117
2011	88.321
2012	89.91
2013	90.118
2014	90.099
2015	89.808
2016	88.898
2017	88.9
2018	88.852
2019	88.805
2020	88.759
2021	88.713
2022	88.67