Price: The Significance of Price Elasticity of Demand (Cambridge (CIE) IGCSE Business)

Revision Note

Danielle Maguire

Written by: Danielle Maguire

Reviewed by: Steve Vorster

An Introduction to Price Elasticity of Demand

  • Price elasticity of demand (PED) measures how responsive demand for a product is to a change in price

    • In most cases an increase in price leads to a fall in demand for a product

    • Similarly a fall in price leads to an increase in demand for a product

  • Price elasticity of demand answers the question of by how much demand changes?

    • Price elastic demand is where the volume of a product's sales changes by a greater percentage than the change in price

      • E.g. A 10% increase in price leads to a 20% decrease in the volume of sales

    • Price inelastic demand is where the volume of a product's sales changes by a smaller percentage than the change in price

      • E.g. A 10% increase in price leads to a 5% decrease in the volume of sales

Calculation of PED

  • Price elasticity of demand is calculated using the formula

begin mathsize 14px style text PED =  end text fraction numerator percent sign space change space in space quantity space demanded over denominator percent sign space change space in space price end fraction space equals space fraction numerator percent sign triangle space in thin space QD over denominator percent sign triangle in space straight P end fraction end style
 

  • PED will always be negative due to the inverse relationship between price and quantity

    • If the price goes up the quantity demanded goes down

    • If the price goes down the quantity demanded goes up

  • The numerical value of PED indicates the responsiveness of a change in quantity demanded to a change in price

Interpretation of PED Values

Numerical Value 

Explanation

Examples

> 1

ELASTIC

  • Demand is more responsive to a change in price

  • The %∆ in QD is more than proportional to the %∆ in P

  • An increase in selling price reduces the total amount of revenue generated from sales

  • A reduction in selling price increases the total amount of revenue generated from sales

  • Luxury products such as cars, smart watches, foreign holidays, cinema visits, jewellery, and branded goods

Between

0 & 1

INELASTIC

  • Demand is less responsive to a change in price

  • The %∆ in QD is more than proportional to the %∆ in P

  • An increase in selling price increases the total amount of revenue generated from sales

  • A reduction in selling price reduces the total amount of revenue generated from sales

  • Necessities such as bread, milk, eggs, and potatoes; fuel; rent; toothpaste, etc.

  • Addictive products such as cigarettes and sugary foods

The Significance of Price Elasticity of Demand

  • If businesses can determine the price elasticity of demand for their products, they can adjust their pricing strategy to maximise their revenue

  • If the demand for their products is relatively price inelastic (PED < -1), raising the price will lead to an increase in total revenue. However, lowering the price will lead to a fall in total revenue

    • Price skimming strategies are best employed for products that are price inelastic in demand

  • If demand for their products is relatively price elastic (PED > -1), raising the price will lead to a fall in total revenue. However, lowering the price will lead to a rise in total revenue

    • Competitive pricing strategies are best employed for products that are price inelastic in demand

The Relationship Between Price Elasticity of Demand and Total Revenue

Price elastic demand

  • The ratio outcome is greater than 1 (Between 1 and ∞)

  • An increase in price will lead to a decrease in revenue

  • A decrease in price will lead to an increase in revenue

screen-shot-2023-02-27-at-3-15-24-pm

Price inelastic demand

  • The ratio outcome is between 0 and 1

  • An increase in price will lead to an increase in revenue

  • A decrease in price will lead to a decrease in revenue

screen-shot-2023-02-27-at-3-15-58-pm

Factors Influencing the Price Elasticity of Demand

Diagram: PED influencers

Factors Influencing the Price Elasticity of Demand
The factors which determine if a product is more price elastic or price inelastic in demand

Brand loyalty

  • The aim of advertising and marketing expenditure by a business is to shift the demand curve to the right and make the demand more price inelastic

    • E.g. Coke consumers tend to remain brand loyal to Coke and are unlikely to buy Pepsi even though their taste and selling price are very similar

Availability of substitutes

  • Demand for goods that have fewer substitutes is likely to be price inelastic

    • E.g. Petrol has fewer substitutes and is more price inelastic whereas chocolate bars have more substitutes and are more price elastic

The proportion of income taken up by the product

  • The smaller the proportion of income we spend on a product the more price inelastic the demand will be

    • E.g. A small amount of income is spent on salt and so demand for salt is more price inelastic whereas buying a new car takes up a bigger proportion of consumer income and so demand is more price elastic

Luxury or necessity

  • Necessities are required as part of consumers' daily needs and are therefore more price inelastic in demand

    • E.g. Bread, milk, petrol, gas and electricity might be considered to be necessities

  • Luxuries are not essential and are therefore more price elastic in demand

    • E.g. Smoked salmon, Nike Air Jordans, and foreign holidays might be considered to be luxuries

Time

  • The longer the time period under consideration the more price elastic the demand for a good or service is likely to be (consumers have more time to search for substitutes)

  • The shorter the time period under consideration the more price inelastic the demand for a good or service is likely to be

    • For example, if the price of petrol increases, making driving more expensive, there is little that consumers can do in the short term but pay the price required to keep their vehicle running

    • Over time they may switch to alternatives such as public transport or bicycles so demand for petrol could be more price elastic in the long-term

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Danielle Maguire

Author: Danielle Maguire

Expertise: Business Content Creator

Danielle is an experienced Business and Economics teacher who has taught GCSE, A-Level, BTEC and IB for 15 years. Danielle's career has taken her from across various parts of the UK including Liverpool and Yorkshire, along with teaching at a renowned international school in Dubai for 3 years. Danielle loves to engage students with real life examples and creative resources which allow students to put topics in a context they understand.

Steve Vorster

Author: Steve Vorster

Expertise: Economics & Business Subject Lead

Steve has taught A Level, GCSE, IGCSE Business and Economics - as well as IBDP Economics and Business Management. He is an IBDP Examiner and IGCSE textbook author. His students regularly achieve 90-100% in their final exams. Steve has been the Assistant Head of Sixth Form for a school in Devon, and Head of Economics at the world's largest International school in Singapore. He loves to create resources which speed up student learning and are easily accessible by all.