Year	Percent
1990	98.942
1991	98.978
1992	98.982
1993	98.981
1994	98.989
1995	98.99
1996	98.997
1997	98.996
1998	98.994
1999	98.989
2000	98.982
2001	98.974
2002	99.037
2003	99.011
2004	98.999
2005	98.988
2006	98.996
2007	98.991
2008	98.966
2009	98.91
2010	98.805
2011	98.481
2012	98.039
2013	98.178
2014	98.208
2015	98.122
2016	98.094
2017	98.015
2018	97.937
2019	97.858
2020	97.779
2021	97.701
2022	97.624
2023	97.546
2024	97.47
2025	97.395
2026	97.321
2027	97.248
2028	97.175
2029	97.103
2030	97.029