Holdings
1963(1965),2; 1964(1966),2; 1965(1967),3; 1966(1968),2; 1967(1969),2; 1968(1970),2; 1983(1985),2; 1984(1986),2; 1985(1987),2; 1987(1989),2-3; 1988(1990),2-3; 1990(1992),2-3; 1991(1993),2-3; 1992(1994),2-3; 1993(1995),2-3; 1994(1996),2-3; 1995(1997),2-3; 1996(1998),3-4