BharatNotes What is the Gini Coefficient?
The Gini Coefficient is a number between 0 and 1 (often expressed as 0–100, the Gini index) that summarises how unequally income or consumption is spread across a population. A value of 0 means perfect equality — every person or household has an identical share. A value of 1 (or 100) means perfect inequality — a single person holds all the income while everyone else has nothing. Real economies lie between these extremes.
It is calculated from the Lorenz curve, which plots the cumulative percentage of total income (vertical axis) against the cumulative percentage of the population ranked poorest-to-richest (horizontal axis). The Gini Coefficient equals the area between the 45-degree line of perfect equality and the Lorenz curve, divided by the entire area beneath the line of equality. The further the Lorenz curve sags below the equality line, the higher the Gini.
Key Features and Limitations
| Feature | Detail |
|---|---|
| Origin | Devised by Corrado Gini, 1912 |
| Scale | 0 (perfect equality) to 1/100 (perfect inequality) |
| Basis | Income, consumption, or wealth distribution |
| Source data | Household surveys (e.g. India's HCES; World Bank PIP) |
| Strength | Single, comparable, intuitive summary number |
| Weakness | Insensitive to where in the distribution inequality occurs; consumption-Gini understates true gaps |
A major caveat: a Gini built on consumption expenditure (poor people spend most of what they earn; the rich save) reads far lower than one built on income or wealth. The two are not comparable across countries that use different bases.
Current Status — India
India's consumption-based Gini fell from 28.8 (2011-12) to 25.5 (2022-23), per the World Bank's Poverty & Equity Brief (April 2025), placing India among the world's most equal economies on this measure. Over the same period extreme poverty (at the $2.15/day line) fell from 16.2% to 2.3%, lifting about 171 million people out of extreme poverty.
However, income- and wealth-based measures tell a sharply different story. The World Inequality Lab (Piketty, Bharti, Chancel et al., 2024) estimates India's income Gini at ~0.61 (2022-23), with the top 1% taking 22.6% of national income and 40.1% of wealth — the highest shares recorded in over a century. This "consumption vs income" divergence is the single most exam-worthy nuance.
UPSC Angle
For Prelims, know the 0-to-1 scale, the Lorenz-curve linkage, and that 0 = equality. For Mains GS3, deploy the Gini to argue about inclusive growth, jobless growth, and redistribution — always date-stamping figures and flagging the consumption-vs-income gap. Do not confuse the Gini Coefficient with the Palma ratio (top 10% vs bottom 40%) or the Kuznets curve (the inverted-U hypothesis that inequality first rises then falls with development). For current-affairs integration, cross-link inequality debates and the latest Economic Survey data to Ujiyari.com.
Foundation concept — no direct PYQ on the exact term; underpins multiple GS3 questions on inequality, inclusive growth and redistribution.
