Income quintiles

Household income is an economic measure that can be applied to one household, or aggregated across a large group such as a county, city, or the whole country. It is commonly used by the United States government and private institutions to describe a household's economic status or to track economic trends in the US.

Household income is measured in various ways. One key measure is the real median level, meaning half of households have income above that level and half below, adjusted for inflation. According to the Federal Reserve, this measure was $56,516 in 2015, up $2,798 or 5.2% from the 2014 level of $53,718. This was the largest one-year percentage increase on record. However, it remained 2.5% below the 1999 peak of $57,909. The Census Bureau estimated real median household income at $55,775 in 2015, up $2,062 or 3.8% from the 2014 level of $53,713. Household income varies geographically and by race. The overall median has continued to rise steadily, if slowly, to $57,616 in September 2016 according to one unofficial source that reports monthly versus annually.

The distribution of U.S. household income has become more unequal since around 1980, with the income share received by the top 1% trending upward from around 10% or less over the 1953–1981 period to over 20% by 2007. After falling somewhat due to the Great Recession in 2008 and 2009, inequality rose again during the economic recovery, a typical pattern historically.

A household's income can be calculated various ways but the US Census as of 2009 measured it in the following manner: the income of every resident of that house that is over the age of 15, including wages and salaries, or else any kind of governmental entitlement such as unemployment insurance, disability payments or child support payments received, along with any personal business, investment, or other routine sources of income.

The residents of the household do not have to be related to the head of the household for their earnings to be considered part of the household's income. As households tend to share a similar economic context, the use of household income remains among the most widely accepted measures of income. That the size of a household is not commonly taken into account in such measures may distort any analysis of fluctuations within or among the household income categories, and may render direct comparisons between quintiles difficult or even impossible.

The U.S. Census Bureau reported in September 2016 that real median household income was $55,775 in 2015, a 3.8% increase over the $53,713 amount for 2014. This was the third consecutive year with a statistically significant increase by their measure.

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