Year	Percent
1990	85.42
1991	85.306
1992	85.21
1993	84.996
1994	84.702
1995	84.388
1996	84.082
1997	83.812
1998	83.595
1999	83.304
2000	82.942
2001	82.685
2002	82.385
2003	82.104
2004	82.534
2005	82.953
2006	83.362
2007	83.765
2008	85.753
2009	84.075
2010	82.379
2011	81.93
2012	82.4
2013	82.109
2014	82.21
2015	83.39
2016	83.574
2017	83.555
2018	83.538
2019	83.519
2020	83.497
2021	83.471
2022	83.442
2023	83.409
2024	83.372
2025	83.332
2026	83.287
2027	83.238
2028	83.183
2029	83.122
2030	83.053