Year	Percent
1990	76.107
1991	76.107
1992	75.999
1993	75.983
1994	75.867
1995	75.922
1996	75.965
1997	75.993
1998	76.012
1999	75.858
2000	75.657
2001	75.402
2002	75.108
2003	74.8
2004	74.503
2005	74.229
2006	73.999
2007	73.777
2008	73.56
2009	73.338
2010	73.11
2011	72.903
2012	72.687
2013	72.463
2014	72.401
2015	72.354
2016	72.302
2017	72.33
2018	72.355
2019	72.366
2020	72.361
2021	72.346
2022	72.316
2023	72.281
2024	72.254
2025	72.239
2026	72.235
2027	72.235
2028	72.231
2029	72.215
2030	72.184