Gini Coefficient of Household Income Inequality 2005-2007

In comparison to Gini Coefficient of Household Income Inequality from 2011 to 2013

Data Source: American Community Survey (ACS)

Gini Coefficient is a statistical measure that measures household income inequality within a society meaning it measures the extent to which income is distributed in an uneven manner among a population. It is a ratio and ranges between 0 in the case of perfect equality and 1 in the case of perfect inequality i. In other words, it measures the income gap between the wealthy and the poor.

From the top map, we can see a high concentration of dark shaded counties in the southern states indicating and higher proportion of income inequality. In addition, through comparing the two maps we can see in the bottom map that there were more states where counties had extremely low values of income inequality indicated by the “no value” category compared to the top map. This indicates there has been a reduction in household income inequality from 2005 to 2013.


[i] Organisation for Economic Co-operation and Development. “Income Inequality.” OECD 2016. Web. 14 April. 2017.