Year	Percent
1991	91.77
1992	91.76
1993	91.645
1994	91.777
1995	91.54
1996	91.508
1997	91.302
1998	91.587
1999	91.792
2000	91.704
2001	90.849
2002	89.649
2003	90.675
2004	92.502
2005	92.401
2006	92.241
2007	92.265
2008	92.366
2009	91.799
2010	91.821
2011	91.793
2012	91.747
2013	91.405
2014	90.852
2015	91.293
2016	92.519
2017	92.387
2018	92.261
2019	92.17
2020	92.092
2021	92.045
2022	91.998