Census Bureau statistics on income can shed some light on the ongoing debate on income inequality in the United States. Using data from three surveys --- the Current Population Survey Annual Social and Economic  Supplement (CPS ASEC), the American Community Survey (ACS) and the Survey of Income and Program Participation (SIPP) --- reports, tables, graphs and maps summarize the way income and wealth are distributed across the population.

• To examine national trends in income inequality and changes in income inequality since the 1960s, use the CPS ASEC. Estimates from the CPS ASEC going back to 1967 are available in our annual report on Income and Poverty in the United States and in tables found on our website
• The ACS is the best data source for estimates of income inequality at the state, county or local level.  These tables can be accessed using American FactFinder.
• Use the SIPP if you are interested in the distribution of wealth and/or mobility.  SIPP estimates can be found in tables on our website and in special reports and working papers.

For more information on data sources see “Which Data Source to Use” or “Surveys & Programs.”

Two of the most commonly used income distribution measures are the shares of aggregate household income received by each quintile and the Gini index. In addition to these two measures, the Census Bureau also produces estimates of the ratio of income percentiles; the Theil index, the mean logarithmic deviation of income (MLD), and the Atkinson measure.  For complete descriptions of each of these see “Income Inequality Metrics."

Several other federal agencies also publish reports, tables and data on income inequality.  See “Related Sites” to get links to their websites.

For assistance, please contact the Census Call Center at 1-800-923-8282 (toll free) or visit ask.census.gov for further information.