Year	Percent
1990	90.673
1991	91.079
1992	90.946
1993	91.004
1994	89.916
1995	90.148
1996	90.082
1997	89.839
1998	90.063
1999	89.68
2000	89.303
2001	89.003
2002	88.615
2003	88.334
2004	87.854
2005	87.368
2006	87.754
2007	88.224
2008	87.945
2009	87.807
2010	87.23
2011	87.676
2012	87.642
2013	87.561
2014	87.645
2015	87.945
2016	88.233
2017	88.132
2018	88.018
2019	87.9
2020	87.785
2021	87.648
2022	87.508
2023	87.369
2024	87.235
2025	87.108
2026	86.963
2027	86.823
2028	86.691
2029	86.577
2030	86.483