Lorenz Curve - Explained
What is the Lorenz Curve?
Written by Jason Gordon
Updated at March 27th, 2023
- Marketing, Advertising, Sales & PR
- Accounting, Taxation, and Reporting
- Professionalism & Career Development
-
Law, Transactions, & Risk Management
Government, Legal System, Administrative Law, & Constitutional Law Legal Disputes - Civil & Criminal Law Agency Law HR, Employment, Labor, & Discrimination Business Entities, Corporate Governance & Ownership Business Transactions, Antitrust, & Securities Law Real Estate, Personal, & Intellectual Property Commercial Law: Contract, Payments, Security Interests, & Bankruptcy Consumer Protection Insurance & Risk Management Immigration Law Environmental Protection Law Inheritance, Estates, and Trusts
- Business Management & Operations
- Economics, Finance, & Analytics
- Courses
What is the Lorenz Curve?
The Lorenz Curve A Lorenz curve graphs the cumulative shares of income received by everyone up to a certain quintile.
A Lorenz curve shows the cumulative share of population on the horizontal axis and the cumulative percentage of total income received on the vertical axis.
Every Lorenz curve diagram begins with a line sloping up at a 45-degree angle.
The points along this line show what perfect equality of the income distribution looks like. It would mean, for example, that the bottom 20% of the income distribution receives 20% of the total income, the bottom 40% gets 40% of total income, and so on.
The trick in graphing a Lorenz curve is that you must change the shares of income for each specific quintile into cumulative income. For example, the bottom 40% of the cumulative income distribution will be the sum of the first and second quintiles; the bottom 60% of the cumulative income distribution will be the sum of the first, second, and third quintiles, and so on.
In a Lorenz curve diagram, a more unequal distribution of income will loop farther down and away from the 45-degree line, while a more equal distribution of income will move the line closer to the 45-degree line.
The Lorenz curve is a useful way of presenting the quintile data that provides an image of all the quintile data at once.
Related Topics
- Education - Private and Social Rate of Return
- Government Approaches to Encouraging Innovation
- Public Good
- Public, Private, Club, Common Goods
- Excludable and Rivalrous Goods
- What is the Free Rider Problem for Public Goods?
- Free Rider
- Social Loafing
- Role of Government in Paying for Public Goods
- What is the Tragedy of Commons for Common Resources?
- Income Inequality
- Poverty Line?
- Poverty Trap
- Public Safety Net
- Measuring Income Inequality
- Lorenz Curve
- Ladder of Opportunity
- Tradeoff between Incentives and Income Equality
