Population groups of interest to governments and communities usually consist of people who may be disadvantaged compared to the rest of the population in terms of one or more areas of life (e.g. unemployed people are of interest in the area of work). The group might be eligible for a response from the community that would aim to overcome or counteract this disadvantage (e.g. job search allowance, retraining). The ABS has always recognised that its system of social statistics needed to identify groups in society who were vulnerable to and at risk of social disadvantage. However, as noted above, it has become increasingly important to identify these groups in terms of whether they are actual or potential targets for government intervention. During the 1980s, the ABS put effort into ensuring population groups were defined in a standard way in statistical collections. This standardisation meant data about groups of special interest could be brought together from different surveys, or from surveys conducted at different points in time. This allowed the needs of these groups to be analysed in more depth, and for changes in needs that occurred over time to be identified.
The ABS classifies people into population groups based on one or more of their characteristics, such as their age or employment status. For example, the variable 'country of birth' can identify people who have migrated to Australia. When this variable is used in a survey on the labour force, the labour force experience of migrants can be analysed. To further assist analysis, a second variable, ‘period of residence’, can be added. This separately identifies those who have been in the country for some time from those who have just arrived, and can provide insight into why some migrants experience different social problems to others.
Because of their function in describing groups of people, these variables are often referred to as explanatory variables. It is often possible to target a population group so its identifying variables closely align with the eligibility criteria for a planned government service. By analysing data about this targeted group, government planners can estimate potential numbers needing the service, and likely budgetary costs. Data from successive ABS surveys that identify this same population group provide a means of analysing the take up rates of the service and the extent to which the consumption of the service has modified the wellbeing status of the group.
The ABS has collected and published statistics for a wide range of population groups (e.g. long term unemployed, retired people, crime victims, Indigenous people, lone parents). The array of groups identified by the ABS is not based on a fixed or standard list. Its content varies over time, reflecting changing pressures in society and changing needs of statistical users. The content is also a function of the ABS's ability to collect appropriate data about a group. For instance some groups of interest make up so small a proportion of the total Australian population that even large ABS surveys do not encounter enough of them to produce meaningful statistics concerning them. In other cases, where the distinguishing characteristics of a population group are particularly sensitive (e.g. sexual assault victims) it can be difficult to phrase questions, or ensure privacy, in such a way that the group is fully identified.