Question about GAIN Temp Drift of AD8227 and Error Budget Analysis


I would like to ask if someone can explain the negative sign of the GAIN TEMP DRIFT (Gain vs. Temperature) which can be found in the AD8227 Datasheet.

Should one make a valuation of the total Error (in other words an Error Budget) as in Application Note AN-539, should the value of the error be signed, that is NEGATIVE? Which means that it should be subtracted from the Error Budget, fact which seems to be wrong...

Thank you