I would like to enter data in either of two columns and have it appear in the other. Consider a vacation spreadsheet. If "Column A" were hours and "Column B" were Days I would like to enter "8" in "Column A" and have "1" appear in "Column B"; or I would like to enter "3" in "Column B" and have "24" appear in "Column A". How can I do this without getting a circular error?

Thanks Tom G