How does a curve shift differ from quantity demanded or supplied change?
A shift of the supply or demand curve is not the same as a change in the quantity supplied or the quantity demanded. When Demand(D) increases, prices(P) increase and Quantity Demanded (Qd) increases. When D decreases, P decreases and Qd decreases When Supply(S) increases, P decreases and Qd increases When S decreases, P increases and Qd decreases. A change in these curves will cause a new equilibrium to occur. This will cause a change in price and a change in the QUANTITY that is demanded for that good. In other words, many things can cause a change in the demand curve orthe supply curve (i.e. shortages, increased supply costs, decreased income from consumers….) but only ONE THING can change QUANTITY demanded/supplied, and thats PRICE.
