Starling Co. is considering selling a machine with a book value of $20,400 and estimated remaining life of 5 years. The old machine can be sold for $6,000. A new high-speed machine can be purchased at a cost of $70,600. It will have a useful life of 5 years and no residual value. It is estimated that the annual variable manufacturing costs will be reduced from $22,700 to $20,300 if the new machine is purchased. The differential effect on profit for the new machine for the entire 5 years is a(n)