Socio-economic data may be available at a variety of scales, for example: municipalities, regional districts, census tracts, enumeration districts, or at the provincial/state level.

The samples are drawn from one enumeration district (ED) in each area, all the EDs having similar population characteristics.

Its first sentence states that "an enumerator shall be appointed for each enumeration district."

The Registrar General, however, opted for enumeration districts containing less than 1,000 people on average, rather than adopting census tracts.

While tracts composed of enumeration districts were later developed, these were not extensively used.

The Office for National Statistics now uses enumeration districts only for the collection of data, with output areas used as the base unit in census releases.

We were able to obtain data from the 1981 census for enumeration districts (average about 150 households).

Where the population was too small to calculate reliable rates, enumeration districts were combined to form larger areas, in some cases whole wards.

The enumeration districts with sufficient non-whites in them for reliable rates were those with 10 per cent.

The records are indexed only by enumeration district upon initial release; several organizations are compiling indices, in some cases through crowdsourcing.