Although we strive to obtain all demographic and housing data from every individual in the census, missing data are part of every census process. Fortunately, we have long-established procedures we’ve used in previous censuses and surveys to fill in these missing pieces. 

As you’ll see from this blog, this process is complex but is a reflection of the extensive standard statistical methodology we use to account for missing or conflicting data.

We collected demographic and housing data in a few ways:

  • Most people responded online, by phone or by mail and provided their demographic and housing characteristics.
  • A census taker collected the information from the household or group quarters.
  • A census taker collected the information from a proxy, such as a neighbor, landlord or building manager, after multiple failed attempts to reach a household member.
  • We used information the household provided in a previous census, survey, tax return or other government program.

Once we’ve collected all the data we can, we use statistical techniques, such as edits and characteristic imputation, for the small number of missing, invalid, or inconsistent housing or demographic characteristics. With editing, we compare an individual’s responses to those of other household members or the overall group quarters to look for invalid or inconsistent information. With characteristic imputation, we fill in missing information by using a combination of sources, including other information in that individual’s or other family members’ census responses, responses from that individual or family member from another census or survey, or other existing records or information from similar nearby neighbors. More information is available in our blog: How We Complete the Census When Households or Group Quarters Don’t Respond.

It is important to note that edits and characteristic imputation occur after total population counts are finalized — these processes do not affect the number of people counted in the 2020 Census. Also, keep in mind that the Census Bureau receives administrative records from many sources, but the data we collect cannot and will not be shared with anyone else, including other government agencies, or used for anything other than statistical purposes. Statistical purposes never include identifying respondents or the data they provided. 

Census Bureau report. Special Division Chief Roberto Ramirez, Statistician Demographer Christine Borman.