Circular flow of income

The circular flow of income or circular flow is a model of the economy in which the major exchanges are represented as flows of money, goods and services, etc. between economic agents. The flows of money and goods exchanged in a closed circuit correspond in value, but run in the opposite direction. The circular flow analysis is the basis of national accounts and hence of macroeconomics.

The idea of the circular flow was already present in the work of Richard Cantillon.François Quesnay developed and visualized this concept in the so-called Tableau économique. Important developments of Quesnay's tableau were Karl Marx' reproduction schemes in the second volume of Capital: Critique of Political Economy, and John Maynard Keynes' General Theory of Employment, Interest and Money. Richard Stone further developed the concept for the United Nations (UN) and the Organisation for Economic Co-operation and Development to the system, which is now used internationally.

The circular flow of income is a concept for better understanding of the economy as a whole and for example the National Income and Product Accounts (NIPAs). In its most basic form it considers a simple economy consisting solely of businesses and individuals, and can be represented in a so-called "circular flow diagram." In this simple economy, individuals provide the labour that enables businesses to produce goods and services. These activities are represented by the green lines in the diagram.

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