Year	Percent
1990	91.853
1991	91.838
1992	91.839
1993	91.866
1994	91.92
1995	92.014
1996	92.026
1997	92.067
1998	92.13
1999	92.201
2000	92.26
2001	92.285
2002	92.289
2003	92.271
2004	92.258
2005	92.259
2006	92.232
2007	92.263
2008	92.299
2009	92.334
2010	92.367
2011	92.395
2012	91.178
2013	89.759
2014	88.108
2015	88.183
2016	88.27
2017	88.147
2018	88.024
2019	87.903
2020	87.784
2021	87.665
2022	87.547
2023	87.429
2024	87.304
2025	87.171
2026	87.03
2027	86.883
2028	86.732
2029	86.582
2030	86.435