Year	Percent
1990	69.907
1991	69.903
1992	69.875
1993	69.871
1994	69.84
1995	69.808
1996	69.816
1997	69.842
1998	69.848
1999	69.864
2000	69.91
2001	69.9
2002	69.884
2003	69.895
2004	69.901
2005	69.906
2006	69.91
2007	69.91
2008	69.904
2009	69.91
2010	69.908
2011	69.884
2012	69.875
2013	69.871
2014	69.873
2015	69.866
2016	69.86
2017	69.86
2018	69.86
2019	69.86
2020	69.86
2021	69.86
2022	69.86
2023	69.86
2024	69.86
2025	69.86
2026	69.86
2027	69.86
2028	69.86
2029	69.86
2030	69.86