Australian Standard Geographical Classification (ASGC)
The ASGC was the geographical framework formerly used by the ABS for the collection and dissemination of geographically classified statistics. From 1 July 2011 the ASGC has been replaced with the Australian Statistical Geography Standard as the framework for understanding and interpreting the geographical context of ABS statistics, however some statistics will continue to be prepared and disseminated based on ASGC over a transition period.
Australian Statistical Geography Standard (ASGS)
The ASGS brings together all the regions for which the ABS publishes statistics within the one framework and will be used by the ABS for the collection and dissemination of geographically classified statistics from 1 July 2011. It is the current framework for understanding and interpreting the geographical context of statistics published by the ABS.
Refers to the Greater Capital City Statistical Areas of states and territories as defined in the Australian Statistical Geography Standard.
Collection District (CD)
Until the 2006 Census, the smallest geographical area for which Census data were available. From 2011, CDs have been replaced with Statistical Areas Level 1.
Estimated resident population (ERP)
The official measure of the population of Australia, based on the concept of usual residence. It refers to all people, regardless of nationality or citizenship, who usually live in Australia, with the exception of foreign diplomatic personnel and their families. It includes usual residents who are overseas for less than 12 months and excludes overseas visitors who are in Australia for less than 12 months.
Greater Capital City Statistical Area (GCCSA)
Represent the socioeconomic area of each of the eight state and territory capital cities. These boundaries are built from aggregations of whole Statistical Areas Level 4. GCCSA boundaries represent a broad socioeconomic definition of each city, they contain not only the urban area of the city, but also surrounding and non-urban areas where much of the population has strong links to the capital city, through for example, commuting to work.
The difference between two estimates at 30 June of a Census year population: the first based on the latest Census and the second produced by updating from the previous Census-based estimates which do not take account of information available from the latest Census.
Local Government Area (LGA)
An ABS approximation of an officially gazetted LGA as defined by each state and territory local government department. LGAs cover incorporated areas of Australia, which are legally designated areas for which incorporated local governing bodies have responsibility. The major areas of Australia not administered by incorporated bodies are the northern parts of South Australia and all of the Australian Capital Territory and the Other Territories. These regions are identified as 'Unincorporated' in the ABS LGA structure.
For any distribution, the median value is that which divides the relevant population into two equal parts, half falling below the value, and half exceeding it. Thus, the median age is the age at which half the population is older and half is younger.
The smallest geographic region in the Australian Statistical Geography Standard (ASGS) which forms the basis for all the larger regions of the ASGS. They broadly identify land use such as residential, commercial, agricultural and parks. There are approximately 347,000 Mesh Blocks and they cover the whole of Australia without gaps or overlaps.
The difference between the actual Census count (including imputations) and an estimate of the number of people who should have been counted in the Census. This estimate is based on the Post Enumeration Survey. For a category of person (e.g. based on age, sex and state of usual residence), net undercount is the result of Census undercount, overcount, misclassification and imputation error.
Population growth rate
Population change over a period as a proportion (or percentage) of the population at the beginning of the period.
Post Enumeration Survey (PES)
A household survey conducted three to four weeks after the Census, which allows the ABS to estimate the number of people missed in the Census and the number counted more than once. Usually more people are missed than are counted more than once in Australia, leading to a net undercount. Results from the PES contribute to a more accurate calculation of the estimated resident population on Census night, which is then backdated to 30 June of the Census year.
The 2011 Census of Population and Housing forms the base for newly compiled estimates for 30 June of the Census year, which can be compared with the alternative estimates produced by updating the 2006 Census-based estimates. Of these two estimates, the more recent Census-based estimate is assumed to be the true estimate. To overcome the break in continuity that this implies, population estimates for all years in between the two most recent Censuses are then revised. This complete exercise is known as 'rebasing', as the population estimates are compiled from a new base, the most recent Census.
Rest of state
Within each state and territory, the area not defined as being part of the Greater Capital City Statistical Area is represented by a Rest of state region.
The number of males per 100 females in a population.
Statistical Area Level 1 (SA1)
An area defined in the Australian Statistical Geography Standard designed as the smallest unit for the release of Census data. They generally have a population of 200 to 800 people, and an average population of about 400 people. SA1s in remote and regional areas generally have smaller populations than those in urban areas. SA1s aggregate to all Non-ABS ASGS Structures except LGAs and Tourism Regions. There are approximately 55,000 SA1s and they cover the whole of Australia without gaps or overlaps. Population estimates are prepared for SA1s by breaking down estimates from the SA2 level.
Statistical Area Level 2 (SA2)
A general-purpose medium-sized area defined in the Australian Statistical Geography Standard built from whole SA1s. They aim to represent communities that interact together socially and economically. SA2s are based on officially gazetted suburbs and localities. In urban areas SA2s largely conform to one or more whole suburbs, while in rural areas they generally define the functional zone of a regional centre. SA2s generally have a population range of 3,000 to 25,000 people, and an average population of about 10,000 people. There are approximately 2,200 SA2s and they cover the whole of Australia without gaps or overlaps. SA2s are the base unit for preparing sub-state population estimates.
Statistical Area Level 3 (SA3)
An area defined in the Australian Statistical Geography Standard built up from SA2s which provides a standardised regional breakup of Australia. SA3s aim to create a standard framework for the analysis of ABS data at the regional level through clustering groups of whole SA2s that have similar regional characteristics. Their boundaries reflect a combination of widely recognised informal regions as well as existing administrative regions such as State Government Regions in rural areas and Local Government Areas in urban areas. SA3s generally range in population from 30,000 to 130,000 people. There are around 330 SA2s and they cover the whole of Australia without gaps or overlaps.
Statistical Area Level 4 (SA4)
An area defined in the Australian Statistical Geography Standard designed for the output of labour force data and to reflect labour markets. In rural areas SA4s generally represent aggregations of multiple small labour markets with socioeconomic connections or similar industry characteristics. Large regional city labour markets are generally defined by a single SA4. Within major metropolitan labour markets SA4s represent sub-labour markets. SA4s are built from whole SA3s. They generally have a population over 100,000 people to enable accurate labour force survey data to be generated. There are 88 SA4s and they cover the whole of Australia without gaps or overlaps.
Statistical Division (SD)
An area defined in the Australian Standard Geographical Classification which represents a large, general purpose, regional type geographic area. SDs represent relatively homogeneous regions characterised by identifiable social and economic links between the residents and between the economic units within the region, under the unifying influence of one or more major towns or cities. They consist of one or more Statistical Subdivisions and cover the whole of Australia without gaps or overlaps.
Statistical Local Area (SLA)
An area defined in the Australian Standard Geographical Classification that is a Local Government Areas, or part thereof. Where there is no incorporated body of local government, SLAs are defined to cover the unincorporated areas. In Census years, up until the 2006 Census, SLAs consisted of one or more whole Collection Districts. SLAs cover the whole of Australia without gaps or overlaps.
Statistical Subdivision (SSD)
An area defined in the Australian Standard Geographical Classification which represents an intermediate level, general purpose, regional type geographic unit. SSDs consist of one or more Statistical Local Areas and cover the whole of Australia without gaps or overlaps.
Usual residence within Australia refers to that address at which the person has lived or intends to live for a total of six months or more in a given reference year.