Year	Percent
1991	77.649
1992	81.71
1993	82.553
1994	83.785
1995	85.137
1996	85.085
1997	79.148
1998	84.436
1999	82.155
2000	81.858
2001	83.122
2002	84.337
2003	85.701
2004	86.157
2005	86.464
2006	86.144
2007	85.769
2008	84.432
2009	85.573
2010	85.936
2011	85.134
2012	86.062
2013	86.479
2014	87.007
2015	87.095
2016	88.484
2017	88.341
2018	87.99
2019	88.22
2020	88.4
2021	88.434
2022	88.49