Year	Percent
1990	97.132
1991	97.237
1992	97.65
1993	97.697
1994	97.491
1995	97.489
1996	97.678
1997	97.577
1998	97.318
1999	97.144
2000	97.126
2001	96.868
2002	96.533
2003	96.415
2004	96.179
2005	96.061
2006	96.141
2007	96.236
2008	96.209
2009	96.079
2010	96.177
2011	95.922
2012	95.655
2013	95.708
2014	95.521
2015	95.467
2016	95.553
2017	95.491
2018	95.428
2019	95.363
2020	95.294
2021	95.221
2022	95.145
2023	95.068
2024	94.991
2025	94.918
2026	94.848
2027	94.783
2028	94.721
2029	94.659
2030	94.596