Year	Percent
1990	98.793
1991	98.781
1992	98.76
1993	98.728
1994	98.685
1995	98.637
1996	98.599
1997	98.55
1998	98.489
1999	98.415
2000	98.33
2001	98.266
2002	98.125
2003	97.969
2004	97.793
2005	97.595
2006	97.355
2007	97.101
2008	96.83
2009	96.544
2010	96.243
2011	95.913
2012	96.351
2013	96.501
2014	96.372
2015	95.971
2016	95.955
2017	95.845
2018	95.725
2019	95.608
2020	95.513
2021	95.577
2022	95.651
2023	95.7
2024	95.696
2025	95.631
2026	95.583
2027	95.495
2028	95.372
2029	95.235
2030	95.103