Year	Percent
1961	90.91345
1962	90.91345
1963	90.91345
1964	90.91216
1965	90.91345
1966	90.91345
1967	90.91345
1968	90.91345
1969	90.89342
1970	90.9141
1971	90.91345
1972	90.91345
1973	90.91345
1974	90.91345
1975	90.91345
1976	81.13536
1977	81.40872
1978	81.37123
1979	80.59317
1980	80.51175
1981	80.46781
1982	80.47168
1983	80.76313
1984	80.52467
1985	80.51175
1986	80.47556
1987	80.70691
1988	80.92986
1989	81.12244
1990	81.20257
1991	81.50888
1992	79.86746
1993	76.9814
1994	76.55812
1995	76.55812
1996	76.55812
1997	83.29312
1998	83.44886
1999	84.19202
2000	84.31352
2001	84.09347
2002	84.08603
2003	73.50127
2004	73.43635
2005	73.29167
2006	73.66312
2007	73.63275
2008	73.52139
2009	73.36925
2010	73.33885
2011	73.32648
2012	73.24949
2013	73.22527
2014	73.00163
2015	72.99022
2016	72.92368
2017	72.86357
2018	72.84163
2019	72.80329
2020	72.35894
2021	72.31505