How Do You Calculate Percentage When Both Numbers Are Negative?

Oddman answered

You do it the same way you do when both numbers are positive.

You have to decide whether a change from -20 to -15 (for example) is an increase or a decrease. The usual formula will show it like this ...
change% = (new - old)/(old)*100%
= (-15 - (-20))/(-20)*100%
= (5/-20)*100%
= -1/4*100%
= -25% (a 25% decrease)

Oddman answered

Calculate it exactly the same way you do with positive numbers.
%difference = (new - old)/(old)*100%

This may not be a sensible thing to do, unless the nature of the numbers is that they are always negative. It might make sense to talk about a percentage increase in expenses, for example. It probably doesn't make sense to talk about a percentage increase in profit when the net was and is a loss.

How Do You Calculate Percentage When Both Numbers Are Negative?

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