I need a definet anwser

I need want to know how to get negitive interigers for spells (like devotion aura that minuses armor).
I need a spectific anwser, I don't want anwsers like:
You go in to file, or edit, or something like that.
Thanx

Go to: File->Preferences->General Tab->Check Allow Negative Values in Object Editor

This allows negative real values but not integers.
Negative integers in not possible in the Editor without using a custom abilitydata.slk.