Differences in size of primary, secondary and tertiary sectors
Economic Development: Comparing Primary, Secondary and Tertiary Sectors Across Countries
Exam Tip 🚀
When answering questions about sector sizes, remember to:
- Identify the primary, secondary, tertiary sectors.
- Give a real‑world example for each sector.
- Use the formula Sector Share = (Sector GDP ÷ Total GDP) × 100% to calculate percentages.
1. What Are the Three Sectors? 📚
Think of the economy as a three‑layer cake:
- Primary sector – the base layer, where raw materials are extracted or grown (e.g., farming, mining).
- Secondary sector – the middle layer, where those raw materials are turned into finished goods (e.g., factories, construction).
- Tertiary sector – the top layer, where services are delivered (e.g., banking, tourism).
Analogy: Imagine a pizza. The dough is the primary sector, the sauce and cheese are the secondary sector, and the toppings plus delivery service are the tertiary sector.
2. Measuring Sector Size 📊
Sector size can be measured by its contribution to GDP or by the share of employment it provides.
Formula for GDP share:
Sector Share = (Sector GDP ÷ Total GDP) × 100%
Example: If the primary sector contributes $200$ billion to a $1,000$ billion GDP, its share is:
(200 ÷ 1000) × 100% = 20%
3. Sector Size in Developing vs. Developed Countries 🌍
| Country | Primary Sector | Secondary Sector | Tertiary Sector |
|---|---|---|---|
| Kenya (Developing) | 32% | 28% | 40% |
| Germany (Developed) | 3% | 38% | 59% |
Key Observation: In developing economies, the primary sector is larger, while in developed economies the tertiary sector dominates.
Key Takeaway 📌
As a country develops, its economy typically shifts from a primary‑heavy structure to a tertiary‑heavy structure. This transition reflects increased industrialisation and a growing service sector.
4. Quick Quiz for You 🤔
- Which sector would you find most of the jobs in a small fishing village?
- In a tech hub like Singapore, which sector is likely to be the largest?
- Calculate the secondary sector share if it contributes $450$ billion to a $1,200$ billion GDP.
Answer Key:
- Primary sector – fishing.
- Tertiary sector – services (finance, IT).
- Secondary share = (450 ÷ 1200) × 100% = 37.5%
Exam Tip 📝
When you see a question about sector sizes, start by identifying the country’s level of development, then match the sector shares to the typical pattern (primary > secondary > tertiary in developing economies, and the reverse in developed economies).
Revision
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