Introduction: Why Demand Matters
In marketing management, understanding demand is like having a superpower. If you know why customers buy a product and how they will react to a price change, you can make better decisions to grow your business. In this chapter, we will look at what makes demand go up or down and how we can measure "elasticity" to predict the future. Don’t worry if the word "elasticity" sounds like a physics lesson—it’s actually a very simple way of measuring how "stretchy" or sensitive customer behavior is!
1. What Influences Demand?
Demand is the amount of a product that consumers are willing and able to buy at a specific price. It isn’t just about "wanting" something; it’s about having the cash to back it up. Many things can make demand shift:
• Price: Usually, if the price goes up, demand goes down. This is the most direct influence.
• Consumer Income: When people have more money (rising incomes), they tend to buy more. However, as we will see later, this depends on the type of product.
• Tastes and Fashion: Trends change! Think about how demand for reusable water bottles has soared while demand for single-use plastics has fallen.
• Competitor Actions: If a rival business lowers their price or launches a massive social media campaign, your demand might drop.
• Marketing and Branding: Successful advertising (promotional mix) increases brand loyalty and demand.
• Seasonality: Demand for ice cream peaks in July; demand for heavy coats peaks in December.
Quick Review: Demand is influenced by both internal factors (the price you set) and external factors (the economy and competition).
2. Price Elasticity of Demand (PED)
PED measures how much the quantity demanded changes when the price changes. It tells us how sensitive customers are to a price tag.
The Formula
\(Price \text{ } Elasticity \text{ } of \text{ } Demand \text{ } (PED) = \frac{\% \text{ } change \text{ } in \text{ } quantity \text{ } demanded}{\% \text{ } change \text{ } in \text{ } price}\)
How to Interpret the Result
1. Price Inelastic (Result is between 0 and -1):
Customers are not very sensitive to price. Even if the price goes up, they keep buying nearly the same amount.
Example: Petrol or essential medicine. If the price of petrol goes up 10%, you still need it to drive to work, so your demand might only drop by 1%.
2. Price Elastic (Result is "greater" than -1, e.g., -2 or -5):
Customers are very sensitive. A small price rise makes them run away to a competitor.
Example: A specific brand of chocolate bar. If the price rises, you just buy a different brand instead.
Note for Exams: PED results are almost always negative because price and demand move in opposite directions. Most examiners focus on the "size" of the number (the absolute value).
3. PED and Total Revenue
This is the "Golden Rule" for marketing managers. Should you raise your price to make more money, or lower it to sell more units? The answer depends on PED.
• If demand is Inelastic: Raise the price! You will lose a few customers, but the higher price per unit will more than make up for it. Total Revenue increases.
• If demand is Elastic: Lower the price! A small discount will attract a massive flood of new customers. Total Revenue increases.
Common Mistake: Don't assume lowering prices always increases revenue. If your product is inelastic (like salt), lowering the price won't make people buy more—they only need so much salt! You’ll just be selling the same amount for less money, which hurts revenue.
4. Income Elasticity of Demand (YED)
YED measures how much demand changes when consumer incomes change (e.g., during an economic boom or a recession).
The Formula
\(Income \text{ } Elasticity \text{ } of \text{ } Demand \text{ } (YED) = \frac{\% \text{ } change \text{ } in \text{ } quantity \text{ } demanded}{\% \text{ } change \text{ } in \text{ } income}\)
Normal vs. Inferior Goods
• Normal Goods (Positive YED): As people get richer, they buy more of these. This includes things like gym memberships, organic food, or holidays.
• Inferior Goods (Negative YED): As people get richer, they buy less of these because they can now afford better alternatives.
Example: Supermarket "value" ranges or bus travel. During a recession (falling incomes), demand for inferior goods actually goes up as people try to save money.
Did you know? High-end luxury brands have very high positive YED. When the economy is booming, their sales skyrocket!
5. Summary Table for Quick Revision
Scenario: Price Rises
If Elastic (\(>1\)): Demand drops a lot \(\implies\) Revenue Falls.
If Inelastic (\(<1\)): Demand drops a little \(\implies\) Revenue Rises.
Scenario: Income Rises
Normal Good (\(+\) YED): Demand Rises.
Inferior Good (\(-\) YED): Demand Falls.
Key Takeaways for Marketing Managers
1. Know your product: If you have a strong brand with high loyalty, your PED is likely inelastic. This gives you "pricing power"—you can raise prices without losing too many customers.
2. Plan for the economy: If you sell inferior goods, you might actually need to increase production during an economic downturn.
3. Use your Budget: Marketing spend (like advertising) aims to make a product more inelastic by building brand loyalty, so customers don't care as much about the price.
(Cross-reference: To see how businesses use this to set prices, check out the chapter on "Marketing Mix: Product and Price".)