Year	Percent
1990	87.689
1991	87.533
1992	87.382
1993	86.669
1994	82.614
1995	82.082
1996	82.109
1997	81.935
1998	82.951
1999	83.611
2000	84.4
2001	83.576
2002	84.439
2003	83.519
2004	84.909
2005	84.461
2006	85.431
2007	85.349
2008	86.406
2009	86.467
2010	85.26
2011	84.748
2012	84.857
2013	84.846
2014	83.828
2015	83.419
2016	83.875
2017	83.88
2018	83.879
2019	83.88
2020	83.888
2021	83.905
2022	83.929
2023	83.96
2024	83.996
2025	84.037
2026	84.086
2027	84.143
2028	84.206
2029	84.269
2030	84.329