Year	Percent
1958	5
1959	5
1960	5
1961	5
1962	5
1963	5
1964	5
1965	5
1966	5
1967	5
1968	5
1969	5
1970	5
1971	5
1972	5
1973	5
1974	5
1975	5
1976	5
1977	5
1978	5
1979	5
1980	5
1981	5
1982	5
1983	5
1984	5
1985	5
1986	5
1987	5
1988	5
1989	5
1990	5
1991	5
1992	5
1993	5
1998	3
1999	5
2000	5
2001	5
2002	5
2003	5
2004	4
2005	4
2006	4