Year	Percent
1991	87.924
1992	88.239
1993	88.37
1994	88.583
1995	88.72
1996	89.041
1997	89.599
1998	89.648
1999	90.109
2000	90.537
2001	90.544
2002	90.588
2003	90.746
2004	90.884
2005	91.032
2006	91.196
2007	91.396
2008	91.211
2009	90.827
2010	90.885
2011	91.2
2012	91.477
2013	91.566
2014	91.638
2015	91.857
2016	91.897
2017	91.765
2018	91.959
2019	92.11
2020	92.229
2021	92.349
2022	92.46