Year	Percent
1961	44.20138
1962	44.22221
1963	44.24494
1964	44.26388
1965	44.28282
1966	44.30365
1967	44.31691
1968	44.32638
1969	44.34532
1970	44.35479
1971	44.36995
1972	44.39078
1973	44.40025
1974	44.40972
1975	44.43434
1976	44.43434
1977	44.43434
1978	44.43813
1979	44.44003
1980	44.44003
1981	44.44381
1982	44.44381
1983	44.44381
1984	44.44381
1985	44.45328
1986	44.45328
1987	44.47033
1988	44.47033
1989	44.47412
1990	44.74875
1991	44.75822
1992	44.47412
1993	44.93627
1994	44.94574
1995	44.9571
1996	44.99309
1997	44.9268
1998	44.85103
1999	44.8283
2000	44.8302
2001	44.69004
2002	44.80558
2003	44.50063
2004	44.61807
2005	44.55367
2006	44.75065
2007	44.75065
2008	44.5423
2009	44.41919
2010	44.65973
2011	44.41919
2012	44.512
2013	44.50821
2014	44.41843
2015	44.38245
2016	44.2938
2017	44.41919
2018	44.41919
2019	44.41919
2020	44.41919
2021	44.41919