Year	Percent
1990	96.995
1991	97.014
1992	97.01
1993	96.998
1994	96.97
1995	96.926
1996	96.873
1997	96.818
1998	96.771
1999	96.72
2000	96.639
2001	96.556
2002	96.458
2003	96.348
2004	96.23
2005	96.115
2006	96.012
2007	95.91
2008	95.825
2009	95.744
2010	95.979
2011	96.2
2012	96.401
2013	96.583
2014	96.935
2015	96.73
2016	96.881
2017	96.884
2018	96.887
2019	96.891
2020	96.895
2021	96.9
2022	96.907
2023	96.914
2024	96.921
2025	96.927
2026	96.933
2027	96.937
2028	96.94
2029	96.942
2030	96.943