Always Be Negative

[Justinian]

I have a spread with 40 + tenants, filled with rent amounts. Columns B, D, and F always need to be negative. I have to import numbers into these columns each week and I hate changing each cell to negative - it takes too long. I tried custom formatting and that worked except for one thing: The sum formula adding the rows in column G thinks these numbers are positive and it adds them as such.

How can I make this spread so that any number entered into columns B, D, and F are always negative AND have the sum formula adding these rows interpret them as negative?

 

[xenou]

Yep. Recent posts are good on this too. My formula was in error, as it treats all as positive.

My original post:
=SumProduct(ABS(A1:A10))

Amend To:
=-SumProduct(ABS(A1:A10))

Much like pbornemeier's last post.

Or with my helper column example, you'd just be sure the helper column works with the correct sign to make all values negative.