scalage

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun An assessed percentage of the total price or measured amount of goods being shipped or stored, used to figure a deduction from the price or amount to reflect normal shrinkage or depletion of the goods.
• noun The estimated amount of lumber in logs being scaled.

from The Century Dictionary.

• noun In leather manufacturing, an allowance in weight of hides, usually about 15 per cent., made for scalings that may drop off.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun estimation of the amount of lumber in a log
• noun the act of scaling in weight or quantity or dimension