Year	Percent
1990	95.513
1991	95.559
1992	95.483
1993	95.42
1994	95.221
1995	95.044
1996	94.874
1997	94.676
1998	94.422
1999	94.139
2000	93.763
2001	93.507
2002	93.162
2003	92.802
2004	92.313
2005	91.87
2006	91.427
2007	90.831
2008	90.395
2009	90.142
2010	89.824
2011	89.51
2012	89.265
2013	89.033
2014	88.784
2015	88.561
2016	88.254
2017	88.181
2018	88.106
2019	88.028
2020	87.949
2021	87.869
2022	87.786
2023	87.703
2024	87.618
2025	87.534
2026	87.451
2027	87.368
2028	87.284
2029	87.197
2030	87.104