U.S. mean disposable household income by age 2018

This statistic uses the term household instead of the term consumer units used by the BLS, as they stated that they are interchangeable for convenience.
Consumer units are defined by the BLS as:
1. all members of a particular household who are related by blood, marriage, adoption, or other legal arrangements.
2. a person living alone or sharing a household with others or living as a roomer in a private home or lodging house or in permanent living quarters in a hotel or motel, but who is financially independent.
3. two or more persons living together who use their incomes to make joint expenditure decisions. Financial independence is determined by spending behavior with regard to the three major expense categories: housing, food, and other living expenses. To be considered financially independent, the respondent must provide at least two of the three major expenditure categories, either entirely or in part.

The age component of a consumer unit is dependent on the reference person in the survey. The reference person of the consumer unit is the first member mentioned by the respondent when asked "What are the names of all the persons living or staying here? Start with the name of the person or one of the persons who owns or rents the home."

Disposable income equals income after taxes.

Please follow this link to access more information about the methodology of the Consumer Expenditure Survey.