If a judgment for money in a civil case is affirmed, interest at the rate prescribed by law shall be payable from the effective date of the judgment of the trial court. If in a civil case a judgment is modified or reversed with directions that a judgment for money be issued by the trial court, interest on the new judgment at the rate prescribed by law shall be payable from the effective date of the prior judgment which was modified or reversed.
Alaska R. App. P. 509