Introduction

Consumer income plays a significant role in determining the demand for goods and services. When people’s incomes change, their spending patterns often change as well.

Students studying Cambridge O Level Economics 2281 and Cambridge IGCSE Economics 0455 learn how economists measure this relationship using Income Elasticity of Demand (YED).

Understanding YED helps economists and businesses predict how demand will change when incomes rise or fall.

What is Income Elasticity of Demand?

Income Elasticity of Demand measures the responsiveness of quantity demanded to a change in consumer income.

It shows how demand for a product changes when people’s income changes.

YED Formula

The formula for calculating income elasticity of demand is:

YED = Percentage change in quantity demanded
      --------------------------------------
          Percentage change in income

The value of YED helps classify goods into different categories.

Types of Goods Based on YED

Normal Goods

Normal goods have positive income elasticity.

This means demand increases when income increases.

Examples include:

• Clothing

• Electronics

• Restaurant meals

As people earn more money, they usually buy more of these goods.

Inferior Goods

Inferior goods have negative income elasticity.

This means demand decreases when income increases.

Examples include:

• Low-cost food products

• Second-hand goods

• Budget transport options

When incomes rise, consumers often switch to better alternatives.

Luxury Goods

Luxury goods have high positive income elasticity.

Demand for these goods increases significantly when income increases.

Examples include:

• Luxury cars

• Expensive holidays

• Designer clothing

These goods are highly responsive to income changes.

Importance of Income Elasticity of Demand

Income elasticity of demand helps:

✔ Businesses forecast demand changes

✔ Firms plan production levels

✔ Governments analyze consumer spending patterns

✔ Economists study economic growth and development

Companies often use YED when planning new products or entering new markets.

Exam Tips for Students

Students studying O Level Economics (2281) and IGCSE Economics (0455) should be able to:

✔ Define income elasticity of demand

✔ Apply the YED formula

✔ Identify normal and inferior goods

✔ Explain how income changes affect demand

These questions frequently appear in multiple-choice and structured exam questions.

Learn Economics with IVY Online

At IVY Online, students preparing for Cambridge Economics exams can access:

• Concept-based lectures

• Elasticity diagram explanations

• Past paper practice

• Exam-focused revision strategies

This helps students develop a strong understanding of economics concepts.