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Kuznets at 70: the enduring significance of a curve and a hypothesis

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  • James K. Galbraith
  • Ravi Kanbur
  • Kunal Sen
  • Andy Sumner

Abstract

Seven decades ago, Simon Kuznets put forward the hypothesis that as economies developed, national inequality would first increase and then decrease—an inverted U-shape. He provided preliminary evidence for the hypothesis on the basis of the limited data available at the time, and theorized the genesis of the curve as arising from the twin forces of structural transformation of the economy and political economy pressures.

Suggested Citation

  • James K. Galbraith & Ravi Kanbur & Kunal Sen & Andy Sumner, 2025. "Kuznets at 70: the enduring significance of a curve and a hypothesis," WIDER Working Paper Series wp-2025-46, World Institute for Development Economic Research (UNU-WIDER).
    • Handle: RePEc:unu:wpaper:wp-2025-46
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    2. Warr, Peter & Yusuf, Arief Anshory, 2026. "Structural change and income inequality: Evidence from Thailand," Structural Change and Economic Dynamics, Elsevier, vol. 79(C), pages 65-79.

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    JEL classification:

    • D31 - Microeconomics - - Distribution - - - Personal Income and Wealth Distribution
    • O15 - Economic Development, Innovation, Technological Change, and Growth - - Economic Development - - - Economic Development: Human Resources; Human Development; Income Distribution; Migration
    • O40 - Economic Development, Innovation, Technological Change, and Growth - - Economic Growth and Aggregate Productivity - - - General

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