Marginal cost pricing is setting the price of a product at or slightly above the variable cost of producing an additional unit. It is typically used in the short-term when a company has unused production capacity. Economists in the mid-20th century favored marginal cost pricing under perfect competition as it promotes efficiency, but others noted that sellers may not cover fixed costs using this approach. Marginal cost pricing determines the price based on the marginal cost needed for the product to break even or meet a profit target, but managers also consider demand and competition. It has been proposed for public utilities where marginal costs are low, but ignores long-run capacity investment needs.