Understanding the Supplemental DHC File

The S-DHC does what its name implies - it supplements the data we released in May 2023 through the Demographic and Housing Characteristics File (DHC). The DHC provided information about people (age, sex, race, ethnicity, relationship to the householder) and households (household type such as family/nonfamily and owner/renter) - in mostly separate tables.

On the other hand, the S-DHC combines data about people and households in the same tables. Specifically, it provides statistics for the average size of families and households, as well as counts of people living in certain types of households.

For example, from DHC we learned:

• The number of married-couple households that had children living in them.
• The number of households that owned their home with a mortgage or a loan.

In the S-DHC, we'll learn:

• The number of children who lived in married-couple households.
• The average household size of people living in a home that's owned with a mortgage or a loan.

The differences may seem subtle, but combining these details about the structure of households and the people living in them complicates protecting the confidentiality of the data, which we'll talk more about below.

As a result of the need for stronger disclosure avoidance techniques, we are only releasing the S-DHC data at the national and state levels - a decision that enables us to both protect respondent confidentiality and provide quality statistics.