Year	Percent
1990	77.792
1991	77.701
1992	77.615
1993	77.695
1994	77.838
1995	77.982
1996	77.949
1997	77.925
1998	77.978
1999	77.891
2000	77.788
2001	77.538
2002	77.315
2003	77.16
2004	76.962
2005	76.829
2006	76.607
2007	76.4
2008	76.304
2009	76.126
2010	76.097
2011	75.941
2012	75.952
2013	75.932
2014	75.962
2015	75.979
2016	75.955
2017	75.827
2018	75.697
2019	75.565
2020	75.431
2021	75.293
2022	75.155
2023	75.015
2024	74.876
2025	74.737
2026	74.598
2027	74.46
2028	74.324
2029	74.188
2030	74.052