[§557-11] Other property subject to depletion. Except as provided in sections 557-9 and 557-10, if the principal consists of property subject to depletion, including leaseholds, patents, copyrights, royalty rights, and rights to receive payments on a contract for deferred compensation, receipts from the property, not in excess of five per cent per year of its inventory value, are income, and the balance is principal. [L 1973, c 200, pt of §1]