Year	Percent
1990	86.909
1991	86.809
1992	86.641
1993	86.507
1994	86.358
1995	86.158
1996	86.112
1997	85.985
1998	85.819
1999	85.719
2000	85.648
2001	85.71
2002	85.707
2003	85.781
2004	85.803
2005	87.298
2006	88.425
2007	87.752
2008	87.047
2009	86.323
2010	85.566
2011	84.794
2012	88.223
2013	83.603
2014	84.494
2015	85.565
2016	84.962
2017	84.989
2018	85.019
2019	85.069
2020	85.145
2021	85.255
2022	85.39
2023	85.534
2024	85.666
2025	85.775
2026	85.87
2027	85.943
2028	85.995
2029	86.032
2030	86.056