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Income Distribution

The way in which income is divided among individuals or households in an economy.

Quintiles

A method of dividing the income distribution into five equal parts, each representing 20% of the population.

Percentiles

A method of dividing the income distribution into 100 equal parts, each representing 1% of the population.

Top 5%

The highest earning segment of the income distribution, which saw an increase in income share from 16.5% in 1980 to 22.2% in 2013.

Top Quintile

The highest earning 20% of the population, whose income share increased from 44.1% in 1980 to 51% in 2013.

Lorenz Curve

A graphical representation of income distribution that shows the cumulative share of income received by different segments of the population.

Perfect Equality Line

A 45-degree line on the Lorenz curve that represents a situation where income is distributed equally among all segments of the population.

Cumulative Income

The total income received by a certain percentage of the population, calculated by summing the income shares of specific quintiles.

Income Inequality

The unequal distribution of income within a population, which can be illustrated through various graphical methods, including the Lorenz curve.

Cumulative Share of Population

The percentage of the population considered up to a certain point on the Lorenz curve, plotted on the horizontal axis.