Year	Percent
1990	96.94
1991	96.948
1992	96.95
1993	96.961
1994	96.931
1995	96.919
1996	96.927
1997	96.932
1998	96.926
1999	96.96
2000	96.978
2001	97.007
2002	97.037
2003	97.083
2004	97.103
2005	97.092
2006	97.06
2007	96.986
2008	96.926
2009	96.916
2010	96.879
2011	96.841
2012	96.824
2013	96.818
2014	96.801
2015	96.763
2016	96.73
2017	96.685
2018	96.635
2019	96.59
2020	96.557
2021	96.533
2022	96.518
2023	96.511
2024	96.511
2025	96.517
2026	96.531
2027	96.553
2028	96.576
2029	96.594
2030	96.6