Year	Percent
1990	88.197
1991	87.458
1992	87.254
1993	87.275
1994	87.461
1995	87.703
1996	87.127
1997	86.678
1998	86.458
1999	86.479
2000	86.664
2001	85.896
2002	85.398
2003	85.38
2004	85.7
2005	86.165
2006	85.875
2007	85.96
2008	86.329
2009	86.857
2010	87.386
2011	86.647
2012	86.849
2013	86.981
2014	87.059
2015	86.995
2016	86.958
2017	86.952
2018	87.043
2019	87.219
2020	87.472
2021	86.715
2022	86.199
2023	85.891
2024	85.742
2025	85.676
2026	84.976
2027	84.397
2028	83.966
2029	83.701
2030	83.557