MultiWii

I noticed the the GUI when connected to the Mutliwii board that the Altitude shown while sitting on the bench (no motors running) varies between -6.2 and -7.2, is this a result of the accuracy of the sensor or a problem with the sensor?
I have no others to compare this too to know if this is normal behavior.

Thanks

I have similar variations with bmp-085, so i guess that's normal.....