This task arises with historical stock prices - when a stock has had
splits.

We have columns A,B,C,D and E.

For each row in columns A,B,C and D, we want replace the old value in
that row by

New Value = Old value times (Value in column E /value in column D)

This would effectively replace Column D by Column E and scale colums A
B and C.

How can this task be automated (I assume it would need a macro) ?

Thansk for any help.