Lorenz Curve & Gini Coefficient Simulator

Load a country's GDP, population and Gini coefficient — or set your own — and watch the Lorenz curve bow away from the line of perfect equality. Then see exactly how many dollars, on average, someone in each 10% of the population would receive — for Cambridge International AS/A Level Economics and NCEA Level 2/3 Economics.

Country

GDP (NZD bn)

Population (m)

GDP and population are shown in each country's own currency; edit them to explore your own scenario.

Lorenz Curve

Cumulative Share of Income vs. Cumulative Share of Population

0.33

Gini Coefficient

Inequality 0.33

Show Gini Areas (A & B)

A Gini of 0.33 indicates low income inequality, similar to some of the more equal developed economies.

Area A: the inequality gap

Area B: income actually held

Gini = A ÷ (A + B). The more the Lorenz curve bows away from the diagonal, the bigger Area A is relative to Area B, and the higher the Gini coefficient.

Average Income by Population Decile

How GDP, population and the Gini coefficient split total income across ten equal-sized 10% population groups

English	Te reo Māori	中文（简体）	한국어	What it means on this page
Lorenz Curve	no attested term	洛伦兹曲线 (Luòlúnzī qūxiàn)	로렌츠 곡선 (Rorencheu gokseon)	A curve plotting the cumulative share of total income (y-axis) received by the cumulative share of the population (x-axis), ranked from poorest to richest.
Gini Coefficient	no attested term	基尼系数 (Jīní xìshù)	지니 계수 (Jini gyesu)	A single number between 0 and 1 measuring income inequality: the area between the Lorenz curve and the line of perfect equality (Area A), divided by the total area under the line of perfect equality (Area A + B).
Line of Perfect Equality	no attested term	绝对平等线 (Juéduì píngděng xiàn)	완전 균등선 (Wanjeon gyundeungseon)	The 45° diagonal on a Lorenz diagram, showing what perfectly equal income distribution would look like — every 20% of the population holding exactly 20% of income.
Income Decile	no attested term	收入十分位数 (Shōurù shífēnwèi shù)	소득 10분위 (Sodeuk sipbunwi)	One of ten equal-sized 10% groups the population is divided into when ranked by income, from the poorest decile to the richest.
Perfect Equality	no attested term	完全平等 (Wánquán píngděng)	완전 평등 (Wanjeon pyeongdeung)	A theoretical situation (Gini = 0) where every individual or household receives an identical share of total income.
Perfect Inequality	no attested term	完全不平等 (Wánquán bù píngděng)	완전 불평등 (Wanjeon bulpyeongdeung)	A theoretical situation (Gini = 1) where a single individual or household receives all of the economy's income and everyone else receives none.
Income Inequality	no attested term	收入不平等 (Shōurù bù píngděng)	소득 불평등 (Sodeuk bulpyeongdeung)	The extent to which income is distributed unevenly across a population, commonly measured using the Gini coefficient or Lorenz curve.