Year	Percent
1990	78.37
1991	78.311
1992	77.817
1993	77.862
1994	77.785
1995	77.566
1996	77.465
1997	77.382
1998	76.969
1999	76.543
2000	76.096
2001	75.618
2002	75.103
2003	74.567
2004	74.028
2005	73.495
2006	73.776
2007	74.044
2008	74.523
2009	74.225
2010	74.809
2011	75.639
2012	76.483
2013	76.443
2014	76.382
2015	76.489
2016	76.621
2017	76.627
2018	76.62
2019	76.576
2020	76.484
2021	76.36
2022	76.193
2023	75.983
2024	75.726
2025	75.424
2026	75.094
2027	74.719
2028	74.327
2029	73.96
2030	73.643