Change in Supply:

A change in supply on the other hand completely shifts the supply curve either to the right when it is an increase in supply or left when it is a decrease in supply. A

change in supply with demand remaining unchanged will also affect both the equilibrium price and quantity.

An Increase in Supply

If demand remains constant but supply increases, the supply curve will shift completely to the right whiles nothing happen to the demand curve. This will reduce the equilibrium market price and the equilibrium quantity on the other hand will increase.

In Figure an increase in the supply of Amala whilst its demand remains constant will shift its supply curve from S0S0 to S1S1. At the initial equilibrium market price of c5,000, there will be excess supply or surplus of Amala of 30 (70 minus 40) bags. The surplus will cause the market price of Amala to fall to an equilibrium price of c4,000 and the equilibrium quantity will increase from 40 to 60 bags.