How little variation in ARSPD_OFFSET means that preflight calibration of airspeed sensor is a waste of time?

ArduPlane
1

Having checked my logs, I note that ARSPD_OFFSET varies from about 102 to 125. Is this sufficient variation to be worth repeating every flight? How much difference does this magnitude of error make to the indicated airspeed if I didn’t calibrate and the offset was wrong by this much??

Thanks!