Australian Statistical Geography Standard (ASGS)
The ASGS brings all the regions for which the ABS publishes statistics within the one framework and has been in use for the collection and dissemination of geographically classified statistics since 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.
The complete enumeration of a population at a point in time with respect to well-defined characteristics (e.g. Persons, Manufacturing, etc.). When the word is capitalised, "Census" refers to the national Census of Population and Housing.
Estimated resident population (ERP)
The official measure of the population of Australia is based on the concept of usual residence. It refers to all people, regardless of nationality, citizenship or legal status, 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 over a 16-month period. It excludes overseas visitors who are in Australia for less than 12 months over a 16-month period.
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 capital city, they contain not only the urban area of the capital 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.
Intercensal difference is the difference between two estimates at 30 June of a Census year population: the first based on the latest Census, and the second arrived at by updating the 30 June estimate of the previous Census year using population change indicator data. For further information see Population Estimates: Concepts, Sources and Methods (cat. no. 3228.0.55.001).
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 larger regions of the ASGS. They broadly identify land use such as residential, commercial, agricultural and parks. There are approximately 358,000 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 (PES) conducted after each Census. 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, differences in classification between the PES and Census 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)
The Census Post Enumeration Survey (PES) is a household survey conducted following the Census. The PES allows the ABS to estimate the number of people missed in the Census and the number counted more than once or in error. Historically 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 (ERP) for Australia, the states and territories and sub-state areas, which is then backdated to 30 June of the Census year.
Rebasing of population estimates
After each Census, the ABS uses Census counts by place of usual residence which are adjusted for undercount to construct a new base population figure for 30 June of the Census year. Because this new population estimate uses the Census as its main data source, it is said to be 'based' on that Census and is referred to as a population base.
Rebasing refers to the process by which the ABS uses this new base to update all previously published annual sub-state population estimates from the previous census to the most recent census (the intercensal period). For further information on rebasing to the 2016 Census see Australian Demographic Statistics, December 2016 (cat. no. 3101.0), specifically the Feature Article, Rebasing of Australia's Population Estimates using the 2016 Census, and Quality Assurance of Rebased Population Estimates, 2016 (cat. no. 3250.0.55.001).
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 sex ratio relates to 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 Local Government Areas and Tourism Regions. There are approximately 57,500 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. Their aim is to represent a community that interacts 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 2,300 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 to provide 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 360 SA3s 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 of over 100,000 people to enable accurate labour force survey data to be generated. There are 107 SA4s and they 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. For the 30 June reference date, this refers to the calendar year around it.