The UC/L Structure groups CDs together to form defined areas according to population size criteria. The resulting areas are known as Urban Centres or Localities. Population counts (place of enumeration) from the latest Census of Population and Housing are used to define the UC/L Structure which means this classification structure is only current at the time of the Census. Both the Urban Centre and the Locality spatial units are made up of one or more contiguous CDs. As the UC/L Structure relates to CDs within defined areas only, the structure, in aggregate, does not cover all of Australia.
The UC/L Structure is separate from the Main Structure because:
- the boundaries do not generally coincide with SLAs and the higher level spatial units in the Main Structure
- its total area covers only part of Australia.