I have a formula I want to calculate.

There are three cells that have a total percentage possible of 100% just adding them creates results different from what I'm wanting. Here is an example:


F5 = -30%
F6 = 35%
F7 = -35%
F8 =sum(F5:F7) and it reads -30%

What I would like for it to read is -65% to show that out of a possible -100% to 100% the total was -65%

Let me explain the purpose of it and perhaps that will make my intention a bit more clear.

This is going to be used as a evaluation tool. There are employees that are to be graded in three categories each having a weighted percentage and when all are totaled there is a possible positive 100% or negative -100% and percentages in between. In my original scenario the employee had two negative sections and one positive. The negative sections totaled -65% while the positive was 35% There is a total of 100% (granted negative and positive combined).

This will be used as a bonus tool. So in the above scenario the employee lost 65% of the bonus due to negative areas, and retained 35% of the bonus.

Perhaps one way to achieve this, and I'm not sure how to write the formula, would be to say if there are more negative numbers from F5:F7 then add only the negative numbers, however if there are more positive numbers in this range only add the positive. I think that would achieve what I'm trying to do.. perhaps not.

Ideas?