In economics, demand is called elastic demand when quantity demanded changes by a larger percentage than price.
Price elasticity of demand measures how responsive buyers are to a price change. Demand is elastic when the absolute value of the elasticity is greater than 1. For example, if a 10% price increase causes quantity demanded to fall by 20%, demand is elastic. The percentage comparison avoids confusing results caused by measuring goods in different units.
Elasticity often depends on available substitutes, how narrowly the product is defined, and the amount of time consumers have to adjust. A particular brand may have elastic demand because shoppers can switch brands, while demand for a broad category may be less responsive. Luxury goods and products taking a large share of income also often show greater responsiveness.
Elastic demand is different from unit elastic demand, where the percentage changes are equal, and inelastic demand, where quantity changes by a smaller percentage. Because price and quantity move in opposite directions along an ordinary demand curve, price elasticity is usually reported as a negative number, though discussions often emphasize its absolute value.