Year	Percent
1991	80.299
1992	80.547
1993	80.417
1994	81.77
1995	82.31
1996	83.565
1997	84.623
1998	85.655
1999	85.316
2000	85.147
2001	85.965
2002	87.795
2003	88.3
2004	89.007
2005	88.769
2006	88.452
2007	89.514
2008	89.824
2009	91.108
2010	91.493
2011	91.557
2012	91.662
2013	91.359
2014	86.498
2015	86.291
2016	86.389
2017	86.253
2018	86.027
2019	85.6
2020	85.666
2021	85.719
2022	85.847