Year	Percent
1990	96.708
1991	96.667
1992	96.602
1993	96.578
1994	96.564
1995	96.546
1996	97.447
1997	98.072
1998	98.511
1999	98.213
2000	97.065
2001	97.034
2002	96.61
2003	95.456
2004	95.429
2005	95.39
2006	95.351
2007	93.476
2008	93.617
2009	93.281
2010	93.262
2011	93.269
2012	93.262
2013	93.261
2014	93.258
2015	93.247
2016	93.257
2017	93.183
2018	93.103
2019	93.007
2020	92.886
2021	92.792
2022	92.687
2023	92.577
2024	92.47
2025	92.369
2026	92.253
2027	92.139
2028	92.028
2029	91.919
2030	91.812