Year	Percent
1991	90.375
1992	90.151
1993	90.091
1994	89.47
1995	89.803
1996	91.333
1997	90.372
1998	90.428
1999	90.363
2000	90.513
2001	90.245
2002	90.094
2003	90.339
2004	90.185
2005	90.151
2006	90.025
2007	88.778
2008	89.223
2009	89.164
2010	89.158
2011	89.038
2012	89.03
2013	88.896
2014	88.667
2015	89.217
2016	88.893
2017	88.95
2018	88.963
2019	88.95
2020	88.935
2021	88.92
2022	88.902