The sum of the individual net prices for the layers equals the total net price (P'). The different layers relate to different stages of production, parts to subassemblies, to finished product. The cost of each layer is ignored here to make the graph a Cournot (0,1,1) demand curve. Full monopoly gives a lower price than the mixed structure above. Perfect competition in each layer gives a total net price of zero, P' = 0.