But, where focus is on income of persons or households, adjustments to the national accounts or other data sources are frequently used.
Here, interest is often on the fraction of income going to the top (or bottom) x percent of households, the next x percent, and so forth (defined by equally spaced cut points, say quintiles), and on the factors that might affect them (globalization, tax policy, technology, etc.).
Distribution has been central in the study of political economy since the 19th century, as shown in scholarship by Adam Smith, David Ricardo, and John Stuart Mill.
But in the formal theory of social welfare, rules for selection from feasible distributions of income and output are a way of representing normative economics at a high level of generality.
[9] The neoclassical growth model provides an account of how the distribution of income between capital and labor is determined in competitive markets at the macroeconomic level over time with technological change and changes in the size of the capital stock and labor force.