Year	% of total
1960	100
1961	100
1962	100
1963	100
1964	100
1965	100
1966	100
1967	100
1968	100
1969	100
1970	100
1971	100
1972	100
1973	100
1974	100
1975	99.20000000000002
1976	100
1977	100
1978	100
1979	100
1980	100
1981	100
1982	100
1983	100
1984	100
1985	100
1986	100
1987	100
1988	100
1989	100