Year	Percent
1990	89.168
1991	89.148
1992	88.982
1993	88.772
1994	89.01
1995	88.922
1996	88.868
1997	88.73
1998	88.716
1999	88.996
2000	87.912
2001	86.692
2002	85.92
2003	85.119
2004	84.287
2005	83.421
2006	83.473
2007	84.355
2008	85.198
2009	86.006
2010	84.818
2011	83.851
2012	82.812
2013	83.917
2014	84.946
2015	85.9
2016	85.885
2017	85.764
2018	85.643
2019	85.528
2020	85.419
2021	85.317
2022	85.219
2023	85.123
2024	85.027
2025	84.928
2026	84.829
2027	84.728
2028	84.618
2029	84.492
2030	84.344