Use the formula: Price Elasticity of Demand = % change in quantity demanded / % change in price
Calculate the percentage change in quantity demanded
Calculate the percentage change in price
Divide the percentage change in quantity demanded by the percentage change in price
Use the midpoint formula for more accurate results
Compare elasticity values
If the result is greater than 1, demand is elastic
If the result is less than 1, demand is inelastic
If the result equals 1, demand is unit elastic
If the result equals 0, demand is perfectly inelastic
If the result is infinite, demand is perfectly elastic