As shown in the accompanying diagram, a profit-maximizing monopolist produces Q_M, the output level at which MR = MC. A monopolist who mistakenly believes that P = MR produces the output level at which P = MC (when, in fact, P > MR, and at the true profit-maximizing level of output, P > MR = MC). This misguided monopolist will produce the output level Q_C, where the demand curve crosses the marginal cost curve—the same output level produced if the industry were perfectly competitive. It will charge the price P_C, which is equal to marginal cost, and make zero profit. The entire shaded area is equal to the consumer surplus, which is also equal to total surplus in this case (since the monopolist receives zero producer surplus). There is no deadweight loss since every consumer who is willing to pay as much as or more than marginal cost gets the good. A smart monopolist, however, will produce the output level Q_M and charge the price P_M. Profit equals the green area, consumer surplus corresponds to the blue area, and total surplus is equal to the sum of the green and blue areas. The yellow area is the deadweight loss generated by the monopolist.