Year	Percent
1990	97.259
1991	97.27
1992	97.276
1993	97.287
1994	97.292
1995	97.246
1996	97.194
1997	97.135
1998	97.069
1999	96.997
2000	96.919
2001	96.836
2002	96.744
2003	96.641
2004	96.527
2005	96.403
2006	96.268
2007	96.119
2008	96.75
2009	95.361
2010	95.624
2011	95.73
2012	95.402
2013	96.137
2014	94.952
2015	95.912
2016	96.133
2017	96.035
2018	95.937
2019	95.839
2020	95.74
2021	95.64
2022	95.539
2023	95.438
2024	95.336
2025	95.234
2026	95.134
2027	95.036
2028	94.94
2029	94.844
2030	94.748