A sales tax is normally expected to be paid for at least partly by consumers, except in the case when a. demand is perfectly inelastic b. demand is unit elastic c. Buyers and sellers share tax payments. The difference between the maximum amount a consumer would be willing to pay for a given amount of a good and the amount that is actually paid is a. net social cost.
Consumer surplus measures the buyer's gain from a trade.
The more elastic the demand curve, the smaller the area of consumer surplus. Consumer surplus is the benefit to the consumer of being able to purchase one more unit of a market price. Changes in the elasticity of supply will not affect consumer surplus so long as the equilibrium price does not change.