Computing the price elasticity of Demand using the midpoint formula The midpoint formula is preferable when calculating the price elasticity of demand because it gives the same answer regardless of the direction of the change Price Elasticity of Demand (Q2-Q1)(Q2+Q1)2 (P2-P1)[(P2+P1)2Computing the Price Elasticity of Demand Using the Midpoint Formula • The midpoint formula is preferable when calculating the price elasticity of demand because it gives the same answer regardless of the direction of the change. (P P )/[(P P )/2] (Q Q )/[(Q Q )/2] Price Elasticity of Demand = 2 1 2 1 2 1 2 1 − + − +