Year	Percent
1990	76.713
1991	77.016
1992	77.108
1993	76.956
1994	76.565
1995	76.105
1996	75.905
1997	75.615
1998	75.143
1999	74.708
2000	74.451
2001	74.8
2002	75.27
2003	75.812
2004	76.353
2005	76.575
2006	76.838
2007	77.129
2008	76.892
2009	76.655
2010	76.357
2011	76.122
2012	76.008
2013	76.113
2014	75.897
2015	75.551
2016	75.373
2017	75.325
2018	75.28
2019	75.232
2020	75.209
2021	75.294
2022	75.388
2023	75.491
2024	75.617
2025	75.767
2026	76.03
2027	76.312
2028	76.596
2029	76.861
2030	77.102