Year	Percent
1990	94.641
1991	94.692
1992	94.722
1993	94.729
1994	94.695
1995	94.488
1996	94.351
1997	94.309
1998	94.221
1999	93.872
2000	93.5
2001	93.112
2002	92.7
2003	92.265
2004	91.811
2005	91.338
2006	90.839
2007	90.319
2008	89.777
2009	89.206
2010	88.605
2011	87.963
2012	87.289
2013	86.581
2014	85.838
2015	85.059
2016	84.241
2017	84.164
2018	84.088
2019	84.013
2020	83.94
2021	83.867
2022	83.797
2023	83.732
2024	83.676
2025	83.631
2026	83.593
2027	83.564
2028	83.541
2029	83.521
2030	83.5