San Mateo County Gini Index of Income Inequality
The Gini Index, or Gini coefficient, is a statistical measure of distribution that is often used to track economic inequality. It measures how wealth is distributed in a given population. The output is a value between 0 and 1. In San Mateo County and throughout the country, Gini Index is a major focus of the American Community Survey (ACS), conducted each year by the U.S. Census Bureau.
Higher values mean greater inequality. A Gini value of 0 means a perfectly equal society, where everyone's income is the same. A value of 1, on the other hand, represents perfect inequality—a society in which only one person or group has all the wealth. This report uses ACS 5-year estimates for San Mateo County Gini Index data, rather than single-year periods. The 5-year estimates provide greater geographical granularity and accuracy, with a less granular time period.
How does the Gini Index of San Mateo County compare to that of California and the United States?
Note: Use the time-slider beneath the chart to see data from different 5-year periods.
How does Gini Index value vary within San Mateo County, California?
Note: Hover over a census tract in San Mateo County to see its Gini Index.
About the Data
Data is from the U.S. Census Bureau's American Community Survey (ACS), 5-year estimates, table B19083. This report uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.