What it means
Economists measure this with price elasticity of demand, the percentage change in quantity sold divided by the percentage change in price. When the result has a magnitude greater than one, demand is elastic; when it is less than one, demand is inelastic; and at exactly one it is unit elastic.
The sign is almost always negative because price and quantity move in opposite directions, so people usually quote the absolute value. What makes a product elastic is mostly the availability of alternatives.
Branded soft drinks, budget flights on competitive routes and standard commodity components are elastic because a customer facing a price rise has somewhere else to go. Prescription medicines, utilities and specialist industrial spares tend to be inelastic because the customer has no realistic substitute.
The commercial importance is direct. Where demand is elastic, cutting price raises total revenue because the volume gain more than offsets the lower price per unit, and raising price destroys revenue.
Where demand is inelastic the reverse holds, which is why regulated monopolies face price caps. Elasticity is not a fixed property of a product; it shifts with time horizon, customer segment and how big the price move is.
Demand for fuel is inelastic next week and considerably more elastic over five years as people change vehicles, and a business customer on a contract is far less price-sensitive than a walk-in consumer. The trap that catches most commercial teams is confusing revenue with profit.
A price cut in an elastic market reliably grows revenue, but because the cut applies to every unit while variable costs do not fall, contribution can shrink even as the top line grows. The elasticity that matters for a pricing decision is the one measured against gross profit, not sales.
In practice
Real-world examples.
Example
A budget airline drops fares on a route served by three competitors and fills 40% more seats. Because travellers on that route substitute freely between carriers, demand is highly elastic and the load factor responds immediately to any fare move.
Example
A specialist valve manufacturer supplies a component with no approved alternative for a regulated process. It raises prices 8% and loses under 1% of volume, confirming that its demand is inelastic and that pricing power sits with the supplier.
Example
A subscription streaming service tests a $2 monthly increase in one market and sees churn triple among annual-plan customers but barely move among long-tenured monthly subscribers. Elasticity turns out to vary sharply by segment rather than by product.
Formula
Calculation
Price Elasticity of Demand = Percentage Change in Quantity Demanded / Percentage Change in Price
A homeware brand sells a kettle at $50 and moves 20,000 units a quarter. It trials a price of $45 and quarterly volume rises to 26,000 units.
The quantity change is (26,000 - 20,000) / 20,000 = 30%. The price change is ($45 - $50) / $50 = -10%. Elasticity is therefore 30% / -10% = -3, an absolute value of 3, so demand is clearly elastic.
Revenue behaves as the theory predicts: 20,000 x $50 = $1,000,000 before, and 26,000 x $45 = $1,170,000 after, a gain of $170,000. Profit does not. At a variable cost of $30 a unit, contribution was 20,000 x ($50 - $30) = $400,000 and becomes 26,000 x ($45 - $30) = $390,000, so the brand sold 6,000 more kettles and earned $10,000 less.Case study
Seen in the real world.
Meridian Homeware is an invented consumer brand used here as an illustrative case. Facing a flat quarter, its commercial director proposed cutting the price of its best-selling kettle from $50 to $45 on the argument that the category was price-sensitive and volume would follow.
Volume did follow. Quarterly units rose from 20,000 to 26,000, an elasticity of about 3, and revenue climbed from $1,000,000 to $1,170,000. The sales team celebrated and the board was initially pleased.
The finance director then showed the contribution line. With variable cost at $30 a unit, contribution fell from $400,000 to $390,000, because the $5 discount applied to all 26,000 units while the extra 6,000 units each carried only $15 of margin. Meridian reversed the price and instead ran a bundle offer that lifted volume without touching the headline price, and it now models every proposed price change on contribution rather than revenue.
Watch out
Common mistakes.
- Treating a revenue increase after a price cut as proof the decision was right. Elastic demand almost guarantees revenue will rise, while contribution can easily fall at the same time.
- Assuming elasticity is a fixed number for a product. It varies by customer segment, by time horizon and by the size and direction of the price move.
- Estimating elasticity from a single price change during a promotion. Seasonality, competitor activity and advertising all move volume too, so the measured response is rarely attributable to price alone.
Questions
People also ask.
What elasticity value counts as elastic?
Any absolute value above 1, meaning quantity responds proportionally more than price, with values above 2 generally regarded as highly elastic.
Does elastic demand mean I should never raise prices?
No, it means a price rise will cost volume, so the decision turns on whether the higher margin per unit outweighs the units lost, which is a contribution calculation.
Is elasticity different upwards and downwards?
Often yes, since customers tend to react more sharply to increases than to equivalent decreases, so it is unwise to assume a symmetric response.
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