Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

1970

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

1971

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

1972

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

1973

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

1974

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

1975

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

1976

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

1977

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

1978

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

1979

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES

YES