Total revenue is the total receipts a seller can obtain from selling goods or services to buyers. It can be written as P × Q, which is the price of the goods multiplied by the quantity of the sold goods.
A perfectly competitive firm faces a demand curve that is infinitely elastic. That is, there is exactly one price that it can sell at – the market price. At any lower price it could get more revenue by selling the same amount at the market price, while at any higher price no one would buy any quantity. Total revenue equals the market price times the quantity the firm chooses to produce and sell.
As with a perfect competitor, a monopolist’s total revenue is the total receipts it can obtain from selling goods or services to buyers. It can be written as , which is the price of the goods multiplied by the quantity of the sold goods. A monopolist's total revenue can be graphed as in Figure 1, in which Price (P) is the height of the box, and Quantity (Q) is the width. , (i.e., total revenue) equals the area of the box. Letting TR be the total revenue function: , [1] where Q is the quantity of output sold, and P(Q) is the inverse demand function (the demand function solved out for price in terms of quantity demanded). Continuing to use Figure 1 as an example, price can be written as a function of quantity: , and be substituted into TR(Q) to get the TR function , which is a quadratic. In Figures 2 through 4, this function is shown graphically by using an example of demand for apples. The quantity of apples demanded drops as the price increases, which leads to the changes of the total revenue.
The function of TR is graphed as a downward opening parabola due to the concept of elasticity of demand. When price goes up, quantity will go down. Whether the total revenue will grow or drop depends on the original price and quantity and the slope of the demand curve. For example, total revenue will rise due to an increase in quantity if the percentage increase in quantity is larger than the percentage decrease in price. The percentage change in the price and quantity determine whether the demand for a product is elastic or inelastic.
The changes in total revenue are based on the price elasticity of demand, and there are general rules for them: [2]
The above movements along the demand curve result from changes in supply:
Rational people and firms are assumed to make the most profitable decision, and total revenue helps firms to make these decisions because the profit that a firm can earn depends on the total revenue and the total cost.
Total revenue can help with a firm's operational decision: whether the firm should be shut down or kept open.
In the short run, if the total revenue (TR) that a firm can earn from operating will not exceed the variable costs (VC) of operation, the firm should be shut down.
In the long run, a similar rule also can be applied when a firm needs to decide whether it should enter or exit a market. Here physical capital costs are relevant, and together with variable costs they give total long-run costs (TC):
The rules are opposite for entering a market:
A monopoly, as described by Irving Fisher, is a market with the "absence of competition", creating a situation where a specific person or enterprise is the only supplier of a particular thing. This contrasts with a monopsony which relates to a single entity's control of a market to purchase a good or service, and with oligopoly and duopoly which consists of a few sellers dominating a market. Monopolies are thus characterised by a lack of economic competition to produce the good or service, a lack of viable substitute goods, and the possibility of a high monopoly price well above the seller's marginal cost that leads to a high monopoly profit. The verb monopolise or monopolize refers to the process by which a company gains the ability to raise prices or exclude competitors. In economics, a monopoly is a single seller. In law, a monopoly is a business entity that has significant market power, that is, the power to charge overly high prices, which is associated with unfair price raises. Although monopolies may be big businesses, size is not a characteristic of a monopoly. A small business may still have the power to raise prices in a small industry.
In microeconomics, supply and demand is an economic model of price determination in a market. It postulates that, holding all else equal, in a competitive market, the unit price for a particular good or other traded item such as labor or liquid financial assets, will vary until it settles at a point where the quantity demanded will equal the quantity supplied, resulting in an economic equilibrium for price and quantity transacted. The concept of supply and demand forms the theoretical basis of modern economics.
In economics, deadweight loss is the loss of societal economic welfare due to production/consumption of a good at a quantity where marginal benefit does not equal marginal cost – in other words, there are either goods being produced despite the cost of doing so being larger than the benefit, or additional goods are not being produced despite the fact that the benefits of their production would be larger than the costs. The deadweight loss is the net benefit that is missed out on. While losses to one entity often lead to gains for another, deadweight loss represents the loss that is not regained by anyone else. This loss is therefore attributed to both producers and consumers.
In economics, profit maximization is the short run or long run process by which a firm may determine the price, input and output levels that will lead to the highest possible total profit. In neoclassical economics, which is currently the mainstream approach to microeconomics, the firm is assumed to be a "rational agent" which wants to maximize its total profit, which is the difference between its total revenue and its total cost.
In economics, elasticity measures the responsiveness of one economic variable to a change in another. If the price elasticity of the demand of something is -2, a 10% increase in price causes the quantity demanded to fall by 20%. Elasticity in economics provides an understanding of changes in the behavior of the buyers and sellers with price changes. There are two types of elasticity for demand and supply, one is inelastic demand and supply and the other one is elastic demand and supply.
A good's price elasticity of demand is a measure of how sensitive the quantity demanded is to its price. When the price rises, quantity demanded falls for almost any good, but it falls more for some than for others. The price elasticity gives the percentage change in quantity demanded when there is a one percent increase in price, holding everything else constant. If the elasticity is −2, that means a one percent price rise leads to a two percent decline in quantity demanded. Other elasticities measure how the quantity demanded changes with other variables.
In economics, the crosselasticity of demand measures the effect of changes in the price of one good on the quantity demanded of another good. This reflects the fact that the quantity demanded of good is dependent on not only its own price but also the price of other "related" good.
The price elasticity of supply is a measure used in economics to show the responsiveness, or elasticity, of the quantity supplied of a good or service to a change in its price. Price elasticity of supply, in application, is the percentage change of the quantity supplied resulting from a 1% change in price. Alternatively, PES is the percentage change in the quantity supplied divided by the percentage change in price.
In microeconomics, the law of demand is a fundamental principle which states that there is an inverse relationship between price and quantity demanded. In other words, "conditional on all else being equal, as the price of a good increases (↑), quantity demanded will decrease (↓); conversely, as the price of a good decreases (↓), quantity demanded will increase (↑)". Alfred Marshall worded this as: "When we say that a person's demand for anything increases, we mean that he will buy more of it than he would before at the same price, and that he will buy as much of it as before at a higher price". The law of demand, however, only makes a qualitative statement in the sense that it describes the direction of change in the amount of quantity demanded but not the magnitude of change.
A demand curve is a graph depicting the inverse demand function, a relationship between the price of a certain commodity and the quantity of that commodity that is demanded at that price. Demand curves can be used either for the price-quantity relationship for an individual consumer, or for all consumers in a particular market.
Marginal revenue is a central concept in microeconomics that describes the additional total revenue generated by increasing product sales by 1 unit. Marginal revenue is the increase in revenue from the sale of one additional unit of product, i.e., the revenue from the sale of the last unit of product. It can be positive or negative. Marginal revenue is an important concept in vendor analysis. To derive the value of marginal revenue, it is required to examine the difference between the aggregate benefits a firm received from the quantity of a good and service produced last period and the current period with one extra unit increase in the rate of production. Marginal revenue is a fundamental tool for economic decision making within a firm's setting, together with marginal cost to be considered.
The Ramsey problem, or Ramsey pricing, or Ramsey–Boiteux pricing, is a second-best policy problem concerning what prices a public monopoly should charge for the various products it sells in order to maximize social welfare while earning enough revenue to cover its fixed costs.
The tax wedge is the deviation from the equilibrium price and quantity as a result of the taxation of a good. Because of the tax, consumers pay more for the good than they did before the tax, and suppliers receive less for the good than they did before the tax. Put differently, the tax wedge is the difference between the price consumers pay and the value producers receive from a transaction. The tax effectively drives a "wedge" between the price consumers pay and the price producers receive for a product.
The Lerner index, formalized in 1934 by British economist of Russian origin Abba Lerner, is a measure of a firm's market power.
In economics, the total revenue test is a means for determining whether demand is elastic or inelastic. If an increase in price causes an increase in total revenue, then demand can be said to be inelastic, since the increase in price does not have a large impact on quantity demanded. If an increase in price causes a decrease in total revenue, then demand can be said to be elastic, since the increase in price has a large impact on quantity demanded.
In economics, tax incidence or tax burden is the effect of a particular tax on the distribution of economic welfare. Economists distinguish between the entities who ultimately bear the tax burden and those on whom the tax is initially imposed. The tax burden measures the true economic effect of the tax, measured by the difference between real incomes or utilities before and after imposing the tax, and taking into account how the tax causes prices to change. For example, if a 10% tax is imposed on sellers of butter, but the market price rises 8% as a result, most of the tax burden is on buyers, not sellers. The concept of tax incidence was initially brought to economists' attention by the French Physiocrats, in particular François Quesnay, who argued that the incidence of all taxation falls ultimately on landowners and is at the expense of land rent. Tax incidence is said to "fall" upon the group that ultimately bears the burden of, or ultimately suffers a loss from, the tax. The key concept of tax incidence is that the tax incidence or tax burden does not depend on where the revenue is collected, but on the price elasticity of demand and price elasticity of supply. As a general policy matter, the tax incidence should not violate the principles of a desirable tax system, especially fairness and transparency. The concept of tax incidence is used in political science and sociology to analyze the level of resources extracted from each income social stratum in order to describe how the tax burden is distributed among social classes. That allows one to derive some inferences about the progressive nature of the tax system, according to principles of vertical equity.
In economics, demand is the quantity of a good that consumers are willing and able to purchase at various prices during a given time. In economics "demand" for a commodity is not the same thing as "desire" for it. It refers to both the desire to purchase and the ability to pay for a commodity.

In economics, supply is the amount of a resource that firms, producers, labourers, providers of financial assets, or other economic agents are willing and able to provide to the marketplace or to an individual. Supply can be in produced goods, labour time, raw materials, or any other scarce or valuable object. Supply is often plotted graphically as a supply curve, with the price per unit on the vertical axis and quantity supplied as a function of price on the horizontal axis. This reversal of the usual position of the dependent variable and the independent variable is an unfortunate but standard convention.
A markup rule is the pricing practice of a producer with market power, where a firm charges a fixed mark-up over its marginal cost.
In microeconomics, a monopoly price is set by a monopoly. A monopoly occurs when a firm lacks any viable competition and is the sole producer of the industry's product. Because a monopoly faces no competition, it has absolute market power and can set a price above the firm's marginal cost.