1. Imagine that you get a promotion at work and your income increases by 10%.
What will you do with the money?
What products will you buy more of?
Which products will experience the greatest increase in demand?
Will you actually buy less of some products?

2. Income Elasticity of Demand (YED)
Objectives
Define income elasticity of demand (YED), give the equation, explain the possible range of values in relations to luxury goods, normal goods, and inferior goods, and show all of the above in diagrams
Key Concepts
YED
Normal good
Inferior good
Luxury good

3. Definition & Equation
Income elasticity of demand (YED) measures the responsiveness of demand to a change in income
YED = % change in income
% change in demand

4. Two things you must remember…
The sign of the answer
If the YED is positive, an increase in income leads to an increase in demand (and vice versa). Income and Qd move in the same direction. These are normal goods.
If YED is negative, an increase in income leads to fall in demand (and vice versa). Income and Qd move in opposite directions. These are inferior goods

5. Two things you must remember…
The size of the answer
If the YED is greater than 1 it is a luxury good. Here demand is very sensitive to income
If the YED is less than 1 it is a necessity. Here demand is not particularly sensitive to income

6. Why it is important
YED is important to firms because its shows what the effect of income changes might be on demand.
If, for example, an economy is expected to grow faster in the future then the income elasticity should give an insight into what might happen to sales.
This in turn would influence a range of areas, such as staffing levels, cashflow and profit forecasts

7. Different Types of Goods and their Income Elasticity
Normal Luxury
Normal Necessity
Inferior Good
International air travel
Fresh vegetables
Frozen vegetables
Fine wines
Instant coffee
Cigarettes
Luxury chocolates
Natural cheese
Processed cheese
Private education
Fruit juice
Margarine
Private health care
Spending on utilities
Tinned meat
Antique furniture
Shampoo / toothpaste / detergents
Value “own-brand” bread
Designer clothes
Rail travel
Bus travel

8. International Air travel

9. Income Elasticity and the Demand for Airline Travel
Demand for airline travel has a highly positive income elasticity of demand
The industry is cyclical
During an upturn, demand rises for business and leisure travel
During a recession, the demand tails away
In the long run, there is a positive relationship between real GDP per capita and the demand for air travel
Income elasticity will vary according to the type of air travel
E.g. difference between low-cost “no-frills” and higher priced scheduled services on low-haul flights

10. Complete question in chapter 9: Income Elasticity of Demand