Year	Percent
1990	77.723
1991	77.37
1992	77.034
1993	76.705
1994	76.38
1995	76.082
1996	75.873
1997	75.705
1998	75.574
1999	75.475
2000	75.409
2001	75.39
2002	75.556
2003	75.902
2004	76.364
2005	76.852
2006	77.019
2007	77.165
2008	77.301
2009	77.44
2010	76.022
2011	74.424
2012	69.119
2013	74.623
2014	73.791
2015	76.208
2016	76.363
2017	76.543
2018	76.689
2019	76.785
2020	76.824
2021	76.802
2022	76.726
2023	76.614
2024	76.494
2025	76.381
2026	76.264
2027	76.151
2028	76.032
2029	75.888
2030	75.712