composite indicators: Human Development Index (HDI)

Economic Development: Composite Indicators

Human Development Index (HDI)

The HDI is a single number that tells us how well a country is doing in three key areas: health, education, and income. Think of it as a “well‑being score” that helps compare countries beyond just their money.

Exam Tip: When answering questions about HDI, remember to explain the three components and how they are combined into one index. Use the formula to show your understanding of the calculation.

Components of HDI

ComponentIndicatorExampleScale
HealthLife expectancy at birth80 years (high)0–1 (normalised)
EducationExpected years of schooling + Mean years of schooling12 years (expected), 8 years (mean)0–1 (normalised)
IncomeGross National Income per capita (PPP)$30,0000–1 (normalised)

How HDI is Calculated

The HDI is the average of the three normalised indices:

\$HDI = \frac{1}{3}\bigl(I{\text{health}} + I{\text{education}} + I_{\text{income}}\bigr)\$

  1. Normalise each component to a value between 0 and 1.
  2. Sum the three normalised values.
  3. Divide by 3 to get the final HDI.

Analogy: The HDI Smoothie 🌍🍓

Imagine you’re making a smoothie. You need three ingredients: fruit (health), milk (education), and honey (income). Each ingredient has a quality level (0–1). Mix them together in equal parts, and you get a tasty smoothie that represents the country’s overall development. If any ingredient is weak, the smoothie isn’t as good—just like a low HDI score.

Examples of HDI Scores

  • Norway 🇳🇴 – 0.957 (Very high)
  • India 🇮🇳 – 0.645 (Medium)
  • Afghanistan 🇦🇫 – 0.511 (Low)

Exam Tips

- Explain the three components and why each matters for development.

- Show the formula and describe the normalisation process.

- Use real‑world examples (e.g., Norway vs. Afghanistan) to illustrate differences.

- Remember the analogy of the smoothie to help remember the equal weighting of components.

- Answer in clear, concise sentences and avoid jargon that might confuse the examiner.