Year	Percent
1990	96.327
1991	96.408
1992	95.937
1993	96.332
1994	95.821
1995	95.887
1996	96.025
1997	95.552
1998	95.494
1999	95.505
2000	95.336
2001	95.382
2002	95.217
2003	95.257
2004	95.675
2005	95.31
2006	95.273
2007	94.942
2008	93.83
2009	93.373
2010	93.436
2011	93.104
2012	93.784
2013	94.08
2014	93.482
2015	92.535
2016	93.169
2017	93.07
2018	92.984
2019	92.91
2020	92.84
2021	92.76
2022	92.683
2023	92.609
2024	92.537
2025	92.462
2026	92.376
2027	92.292
2028	92.209
2029	92.129
2030	92.051