Most compasses are able to correct for magnetic declination.
Also as the magnetic pole wanders, declination changes about 6 minites a year. Depending on the year the map was published the declinition will be different. Learn how to correct for declinintion and free yourself of gimmicks. Map accessory corrects for magnetic declination when backcountry skiing. Also as the magnetic pole wanders, declination changes about 6 minites a year.