Year	Percent
1991	94.627
1992	95.1
1993	94.737
1994	94.203
1995	92.596
1996	92.283
1997	92.765
1998	92.261
1999	91.765
2000	92.973
2001	92.624
2002	92.23
2003	92.166
2004	92.104
2005	92.055
2006	92.011
2007	91.679
2008	91.665
2009	91.418
2010	90.568
2011	90.268
2012	90.463
2013	89.881
2014	89.399
2015	88.961
2016	88.758
2017	88.715
2018	88.654
2019	88.597
2020	88.541
2021	88.486
2022	88.431