Year	Percent
1961	27.86885
1962	27.86885
1963	29.5082
1964	29.5082
1965	29.5082
1966	29.5082
1967	31.14754
1968	31.14754
1969	31.14754
1970	31.14754
1971	32.78689
1972	32.78689
1973	32.78689
1974	32.62295
1975	32.78689
1976	32.78689
1977	32.78689
1978	32.78689
1979	33.11475
1980	33.60656
1981	34.09836
1982	34.42623
1983	34.7541
1984	35.2459
1985	35.7377
1986	34.7541
1987	34.42623
1988	34.42623
1989	34.42623
1990	34.2623
1991	32.45902
1992	32.29508
1993	32.29508
1994	31.96721
1995	29.5082
1996	28.52459
1997	27.86885
1998	25.40984
1999	25.2459
2000	23.27869
2001	22.78689
2002	21.47541
2003	20.32787
2004	18.19672
2005	17.86885
2006	16.55738
2007	16.27869
2008	16.29508
2009	16.29508
2010	16.29508
2011	16.29508
2012	16.29508
2013	16.29508
2014	16.29508
2015	16.29508
2016	16.29508
2017	16.29508
2018	16.29508
2019	16.29508
2020	16.29508
2021	16.29508