Year	Percent
1991	88.851
1992	85.318
1993	86.004
1994	82.327
1995	80.726
1996	80.609
1997	81.419
1998	83.102
1999	81.69
2000	81.209
2001	81.46
2002	78.672
2003	79.46
2004	78.621
2005	83.561
2006	82.633
2007	82.166
2008	82.589
2009	82.956
2010	83.36
2011	83.436
2012	83.273
2013	82.808
2014	83.206
2015	83.255
2016	83.642
2017	83.705
2018	83.696
2019	83.68
2020	83.659
2021	83.636
2022	83.614