Year	Percent
1991	88.533
1992	88.861
1993	89.485
1994	90.053
1995	90.558
1996	89.648
1997	89.099
1998	88.935
1999	89.148
2000	89.498
2001	88.56
2002	88.346
2003	88.682
2004	89.358
2005	90.176
2006	89.17
2007	88.931
2008	89.231
2009	89.418
2010	90.789
2011	90.848
2012	90.891
2013	91.083
2014	91.456
2015	91.969
2016	91.418
2017	90.813
2018	90.473
2019	90.376
2020	90.425
2021	89.558
2022	88.838