Latest release


Census of Population and Housing: Census dictionary
Reference period

Data processing

Data processing includes all steps from receipt of Census responses in either online or in paper form through to the production of a clean Census data file. 

For 2021 Census, a Data Capture Centre (DCC) was established to register, scan and capture data from the paper forms using imaging and Intelligent Character Recognition. A Data Operation Centre was established which was responsible for processing: including frame reconciliation, coding, imputation, editing, and quality assuring all of the 2021 Census Data.

Derivations and imputations

Derivation is the process where some variables are assigned values based on responses to other questions, or (where no response has been provided) from other family members present in the same dwelling.

Imputation is a statistical process for predicting values where no response was provided to a question and a response could not be derived.

See also Hotdecking.

Destination zone

Destination zones (DZNs) are the spatial unit used to code Place of work (POWP) and are an aggregation of 2021 mesh blocks. DZNs aggregate to statistical areas level 2 (SA2s) in the Australian Statistical Geography Standard (ASGS). Data at DZN level will be available in the Census TableBuilder product.

See also Place of work (POWP) and Australian Statistical Geography Standard (ASGS).


A dwelling is a structure which is intended to have people live in it, and which is habitable on Census night. Some examples of dwellings are houses, motels, flats, caravans, prisons, tents, humpies and houseboats.

Private dwellings are enumerated using online or paper household forms, which obtain family and relationship data as well as information on the dwelling itself such as rent or mortgage payments and ownership. Non-private dwellings (for example hotels and hospitals) are enumerated using online or paper personal forms. While these forms capture information about the person's residential status within the non-private dwelling, they do not capture information on ownership of, or payments related to, the dwelling.

All occupied dwellings are counted in the Census. Unoccupied private dwellings are also counted. This includes unoccupied units in retirement villages (self-contained). Unoccupied residences of owners, managers or caretakers of caravan parks, marinas and manufactured home estates are also counted, but other unoccupied dwellings in such establishments are not counted.

Since the 2001 Census unoccupied private dwellings have been counted in discrete Indigenous communities.

If a non-private dwelling is unoccupied on Census night it is out of scope. Unoccupied residences of owners, managers or caretakers of such establishments are counted.

See also Caravans, Dwelling location (DLOD), Dwelling structure (STRD), Dwelling type (DWTD), Household, Manufactured home estates and Type of non-private dwelling (NPDD).

Dwelling non-response

Dwelling non-response occurs when a private dwelling was identified as occupied on Census night but a Census form was not returned.

The dwelling non-response rate is calculated by dividing the number of non-responding dwellings by all private dwellings identified as occupied on Census night, and is expressed as a percentage.

See also Item non-response and Person non-response.