anchor: For example, if the average piece of mail travels 1,000 miles and that is the cost on which the rate is based, mail going over 1,000 miles gets a relative bargain and mail staying in the office of entry can be viewed as helping to finance the long-distance mail.
positive: Mail that goes long distances receives a comparatively better rate of cost.
negative: Mail that goes long distances receives a comparatively worse rate of cost.