Year	Percent
1991	82.75
1992	82.788
1993	82.378
1994	83.525
1995	82.78
1996	84
1997	84.662
1998	84.187
1999	85.576
2000	85.812
2001	86.557
2002	86.571
2003	86.78
2004	89.456
2005	91.737
2006	90.008
2007	89.559
2008	89.087
2009	88.413
2010	86.93
2011	87.324
2012	87.975
2013	88.665
2014	88.367
2015	88.412
2016	88.762
2017	88.898
2018	88.948
2019	89.032
2020	89.119
2021	89.208
2022	89.305