The Human Development Index and the Gini coefficient
Two numbers beyond GDP: one blends health, schooling and income; the other shows how evenly a total is shared out.
What the paper can ask
- HDI dimensions: life expectancy at birth, mean and expected years of schooling, and GNI per capita at purchasing power parity; an inequality-adjusted HDI was added in 2010.
- The 2025 Human Development Report (2023 data) placed Iceland first with 0.972; ranks 1 to 74 count as very high development. (as of 23 Oct 2026)
- Gini is the area between the line of equality and the Lorenz curve divided by the whole area under the line of equality; a bigger gap gives a higher number.
- Gini: 0 means everyone has an equal share and 1 means one person has everything. It is worked out from the Lorenz curve, which plots the share of the total held by the bottom x of the population.
Why exams ask
Setters ask who created the HDI, its three dimensions, how the Gini coefficient is built and its range.
The full story
The Human Development Index was created for the first Human Development Report in 1990 by Mahbub ul Haq, drawing on Amartya Sen's capabilities approach. It combines life expectancy, schooling (mean and expected years) and income per head, and sorts countries into very high, high, medium and low groups. The Gini coefficient was devised by the Italian statistician Corrado Gini in 1912. It is a number from 0 to 1 (often shown as 0 to 100).
Test yourself
1.The Human Development Index (HDI) is published by:
Correct. The HDI, in UNDP's Human Development Report since 1990, combines life expectancy, education and per capita income.
Not quite. The HDI, in UNDP's Human Development Report since 1990, combines life expectancy, education and per capita income. It goes into your error book.
2.The Gini coefficient measures:
Correct. The Gini coefficient ranges from 0 (perfect equality) to 1 (one person has everything); it is derived from the Lorenz curve.
Not quite. The Gini coefficient ranges from 0 (perfect equality) to 1 (one person has everything); it is derived from the Lorenz curve. It goes into your error book.