VIF 2012 - Frequently Asked Questions
Overview of Victoria in Future 2012
- Important definitions
- What is Victoria in Future 2012?
- What is the purpose of VIF 2012 and who uses it?
- What VIF 2012 products and data are available?
- Which geographical areas are not included in VIF 2012?
- When will VIF 2012 be updated?
- Are these targets for future population and households?
VIF 2012 and other projections and demographic data
- How do the VIF projections differ from other population projections?
- How do population projections differ to the Estimated Resident Population?
VIF 2012 methodology and assumptions
- How are the VIF 2012 projections developed?
- Why does the DPCD produce only one set of projections?
- What assumptions does VIF 2012 make, and what are the influences of these assumptions on the projections?
- How are local conditions taken into account in the projections?
- Are residents in non-private dwellings included in the projections?
- Are international students, business migrants, temporary employer sponsored workers and asylum seekers included in the projections?
- How do the projections account for ‘temporary’ populations, such as those in popular holiday areas?
- Do the VIF 2012 methodology and assumptions differ from those applied to VIF 2008? How do the VIF 2012 projection outcomes compare with VIF 2008?
Commentary on key issues
- What is causing population growth in Victoria?
- Which Victorian areas will grow the most and why?
- Why will the number of households grow at a faster rate than population? Why is the average household size expected to decrease?
- Why is the population ageing?
VIF 2012 refers to the updated population and household projections Victoria in Future 2012 produced by the Victorian Department of Planning and Community Development.
VIF 2008 refers to the previous population and household projections Victoria in Future 2008 which has been superseded by VIF 2012.
Melbourne refers to the Melbourne Statistical Division (Melbourne SD). This region comprises the 31 metropolitan Local Government Areas and excludes the Yarra Ranges Shire Part B Statistical Local Area.
Regional Victoria refers to the part of the state of Victoria outside the Melbourne SD.
The year reference (eg 2011, 2031, 2051, etc) refers to the population at 30 June in that year.
Victoria in Future (or VIF) is the Victorian Government’s official projection of population and households across Victoria. The Spatial Analysis and Research Branch of the Department of Planning and Community Development (DPCD) produces the projections.
VIF 2012 was released in 2012 and is the most updated projections. The projections use the Estimated Resident Population at 30 June 2011 as the base population, and 2012 is the first year of the projected numbers. VIF 2012 supersedes VIF 2008 which was based on the population estimate at 2006.
VIF 2012 shows the quantities and time frames of population changes across Victoria. Specifically, the projections show the changes in population size, age structure, and numbers and types of households over time and space.
The projections give an idea of what is likely to happen if current trends continue. They indicate the possible need for responses to manage change, achieve preferred outcomes or mitigate the impacts of non-preferred outcomes.
State and local governments and agencies use the projections to plan for land use and development, infrastructure, services and programs. Developers and businesses use them to analyse potential markets, for example future demands for dwellings, goods and services and labour supplies.
VIF projections are an important guide for land use planning by State and Local Governments. For example, clause 11.02 of the State Planning Policy Framework explicitly requires planning for urban growth to have consideration to Victorian Government population projections.
All VIF 2012 products and data can accessed via the DCPD’s Victoria in Future website.
The VIF 2012 Brochure is available in electronic format and hard copy. Hard copies can be requested from the DPCD Spatial Analysis and Research Branch.
VIF 2012 products
|VIF 2012 Brochure
||Summary of VIF 2012 highlights, graphs, maps and data
|One-page Profiles (Coming Soon)
||Summaries of VIF 2012 data and graphs for Victoria and each of the Statistical Divisions and Local Government Areas|
||Excel spreadsheets of detailed VIF 2012 data (refer to table below)
|Frequently Asked Questions
||Description of VIF 2012 products, methodology and key demographic trends
VIF 2012 Data Files Victoria
|Geographical Classification||Projection period||Data type||Frequency of data|
|2011 to 2051||Total population (usual residents)
Population by sex and age (1-year & 5-year age groups)
Components of population change
Local Government Area
Statistical Local Area
|2011 to 2031||Total population
Population by sex and age (5-year age groups)
Components of population change
|5-yearly intervals (consistent with Census years)|
Local Government Area
|2011 to 2031||Number of households
Types of households
|5-yearly intervals (consistent with Census years)|
VIF 2012 does not provide projections for the following geographical areas:
- Other states/territories
- Suburbs and towns
- Postcode areas
- Census Collection Districts.
In the past, the DPCD has revised population projections following each national Census. VIF 2012 improves on this process by providing inter-Censal projections based on the latest available Australian Bureau of Statistics’ (ABS) population estimates at 30 June 2011. This ensures that the impact of recent exceptional population growth is taken into account in planning for Victoria’s future.
The DPCD will next update the VIF population and household projections as soon as practicable following the ABS’ release of the 2011 Census data.
VIF 2012 projections are an indication of possible future populations if current demographic, economic and social trends continue. They are not predictions of the future, nor are they future targets.
The projections take into account current government policies that explicitly affect the sizes and distributions of future populations. They do not consider policies that may be introduced in the future.
VIF projections for the different geographical classifications are produced using the same methodology and a consistent set of assumptions. Therefore, comparisons of projections between geographical classifications (such as between a Local Government Area and the state of Victoria, or between regional Victoria and a particular Statistical Division) can be made from a common base.
VIF projections at sub-state geographical classifications equal the Victoria (state) total. Therefore, the sum of the projections for Statistical Local Areas (SLAs) equal the total in the respective Local Government Area (LGA), projections for LGAs sum up to the respective Statistical Division (SD), projections for SDs sum to the respective capital city/balance of state, and capital city and balance of state projections sum to the Victorian total. This is the case for both the population projections and the household projections, as well as their sub-components (age, sex, births, deaths, net migration and household types).
The Australian Bureau of Statistics (ABS) publishes population projections for Australia, its states, territories, capital cities and balances of state. In addition to these geographical classifications, VIF 2012 provides projections of population and households for smaller geographical areas – projections are produced for each of the 11 SDs, the 79 LGAs and the 210 SLAs in Victoria.
While both the ABS and VIF use the cohort component model (which begins with a base population for each year of age and sex and advances it year by year, applying assumptions regarding future fertility, mortality and migration), there are key differences in the way the assumptions are applied, resulting in some differences in the projections produced. However, the VIF 2012 projections use long term assumptions for Victoria that are consistent with the ABS’s series B (medium growth) projections.
Furthermore, the DPCD gathers and analyses information about local land supply and patterns of residential development. This information is a significant input to the VIF 2012 projections. In producing the projections, the DPCD also consults with agencies, such as local governments, that have local knowledge of social and housing development trends. This local knowledge is combined with available information to ensure that the VIF projections are realistic and take into account localised influences on population change.
Some local governments and private businesses also produce population and household projections. These projections may not directly relate to the projections at higher geographical classifications in the same way as the VIF projections. For example, these projections may be produced in isolation so that projections for lower geographical classifications (eg LGAs) may not sum to equal the projections for higher geographical classifications (eg SDs or Victoria).
The DPCD recommends that, regardless of the source of projections used, all data that is being compared should be drawn from the same source to ensure a more valid comparison. This is preferable to comparing the projections from VIF, the ABS and other sources, which may not share common bases, assumptions or methodologies.
The Estimated Resident Population (ERP) is the official measure of the population.
The ERP is based on the concept of usual residence and is usually produced after the reference period (eg the ERP for June 2011 is produced several months after June 2011). It is based on the count from the latest Census and incorporates the estimated Census net undercount (to account for people who were missed from or counted more than once in the Census), and adjusted to include usual residents who were temporarily overseas at the time of the Census and to exclude overseas visitors who were temporarily in Australia on Census night.
The ABS produces ERPs for Australia, its states, territories and sub-state/territory regions (ABS cat. no. 3218.0).
Population projections are estimates of future populations and, unlike the ERP, are produced in advance of the reference period. Projections are developed by applying technical mathematical models and knowledge of likely population trends to the ERP and other existing data.
The DPCD recommends that ERP data is used for research that refers to an earlier time period. Projected data should be used only if the ERP data is not available for the required reference period, or if the data required is for a population at a future time period.
For more information about Estimated Resident Population, refer to the ABS catalogue number 3201.0, available at the ABS website.
The population projections are based on an analysis of existing long and short term trends. The projections are not just an extrapolation of existing trends, but also take account of land availability and redevelopment potential to accommodate new dwellings to house the growing population. This analysis is performed at the statewide, regional and local levels (local level analysis also incorporates detailed knowledge from local governments and other local stakeholders).
Three main methods are used to produce the VIF 2012 population and household projections:
- the Cohort Component method
- the Housing Unit method
- the Household Formation method.
1. The Cohort Component method projects the population by age and sex for each year.
2. The Housing Unit method projects the number of dwellings available in a given area each year.
3. The Household Formation method brings these together by allocating the population into households, based on what we know about household formation patterns, and then placing the households into dwellings (housing units).
The process is then done in reverse as the available dwelling stock in an area will influence the likely households that will move in, and in turn the likely age structure of the population in the area. The whole process requires much iteration of these processes to balance the projections across the 210 Statistical Local Areas in Victoria.
The Cohort Component method involves the fundamental components of population change. It is a purely demographic method that excludes all other external influences such as land availability. It is the most common method used by statistical agencies around the world, including the ABS, to project populations for large geographical areas such as states and territories. (The Housing Unit method, which is driven by a range of external influences, is therefore required to break down large area projections into sensible small area projections.) Using the Cohort Component method, the population in a given area will only be added to through births and in-migration and will only be taken away from through deaths and out-migration.
The Cohort Component method at the state level requires the following inputs:
- base year estimated resident population by age and sex
- age and sex-specific mortality rates
- age-specific fertility rates
- sex ratio for births
- overseas migration arrivals and departures by age and sex
- interstate migration arrivals and departures by age and sex.
The additional input of intrastate (within-state) migration is applied to the Cohort Component method to develop the projections for lower (sub-state) geographical areas.
In VIF 2012, this process has been applied to the 2011 base-year data, and then to the resulting population at the end of each projection year through an iterative process.
The Housing Unit method generates a projection of the number of private dwellings required to house the projected number of households in each Statistical Local Area. It provides a ‘reality check’ about the physical capacity of the existing and potential future dwelling stock to accommodate the projected people and households.
The inputs for the Housing Unit method are:
- base year population
- base year’s stock of structural private dwellings
- new dwelling commencements
- stock loss rates (through demolition or conversion to other uses)
- vacancy rates (dwellings without usual resident households)
- persons in non-private dwellings.
The Household Formation method, developed by McDonald and Kippen in 1998, has been adapted by the DPCD for use in projecting household formation in Victoria. This method is used to aggregate the projected population from the Cohort Component method into households. This also generates the average household size for each year. Persons in non-private dwellings are excluded from this step.
The projection of households developed through the Household Formation method is driven by the age-sex structure of the population (as generated by the Cohort Component method). Effectively, a person’s age and sex is regarded as an indication of their likelihood to be living in a particular type of household.
If a number of projections were made, each one based on different assumptions and scenarios, users of projections may select the set of assumptions or outcomes that most suited their case. This can confuse and lead to technical disputation that would be time consuming and potentially counter-productive.
The DPCD’s approach is to perform sensitivity analyses to produce a single set of reasonable assumptions. This information is strengthened by extensive research on local and regional trends, and by wide consultations with people with specialist and local knowledge, to produce a single set of projections.
What assumptions does VIF 2012 make, and what are the influences of these assumptions on the projections?
The VIF 2012 projections use the Australian Bureau of Statistics’ (ABS) Estimated Resident Population for 30 June 2011 as the base population. This was the most recent population estimate available at the time of developing the VIF 2012 projections. All population and household data from 2012 onwards are projected figures.
Components of population change
Populations grow (or decline) in size from natural increase (number of births minus number of deaths) and net migration (number of people moving in from another area minus number of people moving out to another area). This takes the basic equation:
For each of the four components of population change, one main assumption has been developed at the state level (refer to table below). The assumptions for fertility and migration are then varied when the projections are disaggregated to smaller geographical areas (the assumption for mortality is maintained for all geographical areas). Assumptions for within-state (intrastate) migration are also included in sub-state level projections to take account of local conditions.
The VIF 2012 assumptions are broadly consistent with the ABS’s series B (medium-growth) assumptions.
State-level assumptions applied in VIF 2012
|Component of population change
||Total Fertility Rate (TFR) – the average number of children a woman is likely to have over her lifetime, based on age-specific fertility rates
||Gradual decrease in TFR from 1.77 in 2011 to 1.68 in 2021, remaining constant at 1.68 thereafter
||Age-Specific Death Rate (ASDR) - probability of a person dying during the following year, according to his/her age and sex
||Gradual increase in age-specific life expectancy to 85 years for males and 88 years for females for persons born in 2056
|Net overseas migration (NOM)
||The difference between the number of persons coming to Australia and the number of people leaving Australia, based on the concept of usual residence
||200,000 in 2011
180,000 per year from 2012 onwards
Victoria to consistently receive 27% of national NOM over the projection period
|Net internal migration (NIM)
||The difference between the number of persons coming to Victoria from other Australian states/territories and the number of people leaving Victoria to live in other Australian states/territories
||0 per year
(long-term assumption that annual interstate in-migration will equal out-migration)
Although overseas migration is expected to the largest driver of growth across Victoria over the projection period, the impact of natural increase should not be discounted. Natural increase, or births minus deaths, accounted for 41.2% of Victoria’s population growth in 2010-11 (ABS cat. no.1367.2).
The fertility rate represents the number of children (live births) a female would bear. VIF 2012 uses age-specific fertility rates (ASFR) to project the number of births each year. The ASFR, in effect, is the likelihood of a woman of a given age to have a child. For each year of the projections, the ASFR is applied to all females of child-bearing age to estimate the number of births for each year of the projections. The sum of all ASFR gives the Total Fertility Rate (TFR) which represents the average number of children a woman is projected to have over her lifetime. VIF 2012 adopts a medium-growth scenario fertility assumption through which TFR will gradually decrease from 1.77 in 2011 to 1.68 by 2021 and remain constant thereafter.
The TFR is useful for explaining the year to year fluctuations in fertility, but does have some limitations. Influences on fertility are complex and interact to varying degrees over time. It is difficult to measure the impact of any one influence. This makes projecting fertility patterns challenging, particularly when fertility is strongly affected by economic and social conditions which themselves can be highly volatile and unpredictable. However, the combination of strong population growth and substantial numbers of women in the childbearing age groups projected for the future will result in relatively high (and increasing) numbers of births in Victoria.
There are also considerable variations in the fertility rates in different Victorian regions. Generally the more urban the region, the lower its fertility rate. Melbourne has the lowest rate, followed by the three largest regional centres: Geelong, Ballarat and Bendigo. VIF 2012 assumes that these spatial differences in TFR will continue into the future.
Life expectancy (the average age to which a person is likely to live) has been increasing steadily in Victoria over the past century. With advances in life-prolonging medicines and technologies, reductions in premature life-ending events (eg infant mortality, road accidents, preventable diseases) and overall better health in the community, the trend of increasing longevity is expected to continue, albeit at a reduced rate. Life expectancy for those born in 2056 is expected to have increased to 85 years for males and 88 years for females.
The Age-Specific Death Rates (ASDR) used in VIF2012 are consistent with these assumptions (and also the ‘medium’ life expectancy assumption used by the ABS in its projections). While there are regional variations in mortality rates, the data is too volatile to exhibit useable trends. Hence, regional differences in ASDRs have not been incorporated in the VIF 2012 projections.
Despite the expected increases in life expectancy, the number of deaths in Victoria is projected to continue to rise, primarily due to the larger population base – over time there will be more people in the older age groups and, therefore, more deaths.
Net overseas migration
Net overseas migration (NOM) is the difference between people coming to live in Australia and residents leaving to settle overseas.
Over the last 20 years, natural increase has generally contributed more to Australia's annual population growth than overseas migration. However, in the past four years, overseas migration has overtaken natural increase as the major contributor to population growth. In 2009-10, NOM accounted for around 60.8% of the annual population growth in Victoria (ABS cat. no. 1367.2).
It is important to note that NOM is not necessarily the same as permanent migration. The 12/16 month rule is applied as the criterion for inclusion (or exclusion) in the population estimates and, by extension, the population projections. Under this rule, an individual is required to live in Australia for at least 12 months out of the past 16 months to be considered a ‘usual resident’. This 12 month period does not have to be continuous.
In recent years, the largest contribution to NOM has been from people on temporary visas. In 2007-08, this group accounted for two-thirds of Australia’s NOM. Students were the largest category of temporary net migration, comprising 39% of all NOM over this period. The number of overseas students contributing to Australia’s NOM has more than doubled from 45,300 in 2004-05 to 108,700 in 2007-08 (ABS cat. no. 4102.0).
Information produced by the ABS since the release of the VIF 2008 projections shows that actual NOM in Australia peaked at 315,000 in the 2008 calendar year and has now decreased to around 170,000 in 2011.
In preparing the VIF 2012 projections, the NOM assumption for Australia has been set at a constant 180,000 persons per year from 2012 onwards. This is consistent with the NOM assumption applied in recent Commonwealth Treasury’s published projections and the ABS's projections (series B assumptions).
Overseas migration can vary greatly from year to year, although the variations tend to follow cyclical patterns and are often closely linked to economic conditions, with migration generally running at higher levels during strong economic times and falling away during economic downturns. While future changes to economic conditions and government policy may change the levels of migration in shorter cyclical patterns, over the long term the migration assumption of 180,000 persons per annum remains a realistic view of future net migration to Australia.
Victoria’s share of overseas migration to Australia varies a small amount over time. VIF 2012 projections assume that Victoria’s share of NOM will remain constant at 27% per year. According to the last Census, over 90% of overseas migrants to Victoria settled in Melbourne. Furthermore, as the age distribution of net overseas migrants is significantly younger than that of the established population, NOM is expected to boost the numbers and proportions of people in the younger age groups in Melbourne and, in time, Melbourne’s level of natural increase (ie birth/death ratio). This will contribute to maintaining Melbourne’s younger age structure relative to regional Victoria.
Net interstate migration
Much of the Australian population relocates interstate each year and the net flows between states and territories can greatly influence their overall population growth. Simply derived from summing total arrivals and departures in each state or territory (as measured by the ABS), net interstate migration (NIM) can vary greatly from year to year. Relative to the other components, NIM is a minor component of population change in Victoria. In 2010, NIM accounted for only 3.5% of Victoria’s population growth.
VIF 2012 applies a NIM assumption of zero for the entire projection period. This reflects the trend since 1998 of relatively equal flows of interstate migrants in and out of Victoria (annual flows of around 60,000 to 70,000 people in each direction). Additionally, as the age structures of exiting and entering interstate migrants are not significantly different, NIM is not expected to have a marked effect on the projected population.
It is possible that at some point in the future Victoria will return to the losses of the past, but the zero assumption is a reasonable indication of the state’s gains and losses balancing out over the long-term.
The DCPD takes into account local conditions and differences in developing the VIF 2012 projections. In terms of the four components of population change, VIF 2012 applies the same assumptions relating to mortality across all localities. However, in developing sub-state level projections, locally-specific fertility rates are used and significant migration patterns and trends affecting the local area are also taken into account.
One key input to the VIF projections is the availability of land and housing, including data on local vacancy rates, recent development trends and capacities for additional dwellings. The DPCD’s Urban Development Program (UDP) provides updated analysis on the supply of and demand for residential and industrial land across the metropolitan Melbourne and Geelong regions over the short to medium term. In developing the VIF projections, the DPCD takes into consideration the UDP information as well as information gathered through consultations with local governments and other stakeholders who have localised knowledge.
Yes. The numbers and demographics of people living in non-private dwellings are explicitly calculated and considered in developing the VIF 2012 projections.
In producing the projections for each Statistical Local Area, allowance is made for known sizeable institutions (such as corrective institutions, staff quarters, boarding schools, and residential aged care facilities that are not self-contained). Notable demographic characteristics of these resident groups are also factored into the projections (for example, the potential influence of an institution that houses a substantial number of young people on the overall age-specific migration propensity of the area’s population).
Are international students, business migrants, temporary employer sponsored workers and asylum seekers included in the projections?
Yes, no, maybe.
The VIF projections include all people who are considered to be ‘usual residents’. This is measured by the 12/16 month rule where a person is regarded as a usual resident in Australia if they have stayed in Australia for a period of 12 months or more over a 16 month period, and is not considered to be a usual resident if they are absent from Australia for 12 months or more over a 16 month period. Critically, this 12 month period does not have to be continuous.
Prior to the introduction of the 12/16 month rule by the Australian Bureau of Statistics in September 2006, the 12/12 month rule was used and required a continuous 12 month stay. The revised criterion makes allowances for brief and temporary periods of return to the country of origin, which can be a common pattern for some long-stay migrant groups such as overseas students, business migrants and temporary employer sponsored workers.
Asylum seekers are not authorised arrivals and do not yet have a visa to remain in Australia. Despite this, they are counted in net overseas migration statistics and therefore may be included in population estimates and projections.
The VIF 2012 projections are based on the usual resident population and not on seasonal, temporary fluctuations. People are counted based on to their place of usual residence.
Holiday destinations, such as many Victorian coastal and riverfront areas, often have high seasonal populations with, consequently, low dwelling occupancy rates for most of the year. While the occupancy rates in most Victorian coastal towns are increasing as permanent settlement in these areas grows, it is not uncommon to have winter occupancy rates well under 50% in some locations. VIF 2012 provides projected occupancy rates for all geographical classifications from 2011 to 2031. These occupancy rates reflect the relationship between private dwellings and usual resident households, and gives an indication of holiday areas that may experience seasonal changes in population.
Users of VIF 2012 projections should be aware of these possible seasonal changes and may need to apply local knowledge to the projections to suit their particularly purposes. For example, businesses and organisations providing services may need to be aware of both the usual resident and holiday peak populations in their business/service planning.
Do the VIF 2012 methodology and assumptions differ from those applied to VIF 2008? How do the VIF 2012 projection outcomes compare with VIF 2008?
VIF 2012 updates VIF 2008 and uses the same methodology and similar assumptions, with the exception of net interstate migration.
For more than a decade, net interstate migration to Victoria had been hovering around zero, the largest movement being a loss of 6,200 people in 1996-97. Since January 2009, Victoria has gained a few hundred people each quarter. VIF 2008 applied a long-term assumption of -6,000 each year (ie an annual net loss of 6,000 people due to migration to other states/territories). While small variations up and down are expected, their timing is unpredictable. VIF 2012 has applied a long term assumption of zero net interstate migration.
Although the rate of change in the Total Fertility Rate (TFR) has been as projected in VIF 2008, the base TFR of 1.77 used in VIF 2012 is higher than the actual projected TFR in VIF 2008 for the same period. This results in a higher number of births over time.
Since the release of VIF 2008, there has been exceptional population growth in Victoria. As a result, the ABS estimate of Victoria’s population for 2011 exceeded the VIF 2008 population projection by 72,000. The VIF 2012 base population is the preliminary estimated population at 30 June 2011. VIF 2008 projected Victoria’s population to be 5.55 million at 2011, growing by 2.7 million to 8.27 million by 2051. In comparison, VIF 2012 starts with a larger base population than VIF 2008 and projects a slightly greater growth rate and larger population size. Under VIF 2012, Victoria’s population is projected to increase from 5.55 million in 2011 to 8.73 million in 2051.
In terms of the spatial distribution of population change, the most notable difference from VIF 2008 is the increased rate of projected growth in Melbourne’s inner west. At the Local Government Area level, the most notable changes from VIF 2008 are in the Shire of Mitchell (particularly the southern part of the municipality that was brought into the Urban Growth Boundary in 2010) and the City of Latrobe. Both of these areas have experienced greater growth since 2008 than anticipated under the previous projections.
In regional Victoria, growth in the Mallee and Wimmera regions has been stronger than projected under VIF 2008, primarily due to stronger than projected growth in the major centres of Horsham and Mildura. The Wimmera has also turned around from experiencing small losses to small gains, a result of slower population loss in rural areas than projected under VIF 2008.
VIF 2012 projects a slightly younger age structure for Victoria’s population than that projected under VIF 2008. This is mainly due to the recent increase in in-migration and the younger age profile of immigrants compared with the existing population. Under VIF 2012, approximately 60% of Victorians will be aged 18 to 64 years at the year 2036, compared with the VIF 2008 projection of 58%.
The major driver of population growth in Victoria over the projection period will be net overseas migration (NOM). NOM is expected to add approximately 1.94 million net people to Victoria’s population from 2011 to 2051, while natural increase (births minus deaths) is projected to add 1.15 million net people.
The number of births per annum in Victoria is projected to increase from 72,000 in 2011 to 94,000 in 2051. The number of deaths is also expected to increase, from 35,000 in 2011 to 76,000 in 2051. Thus, natural increase is projected to decrease from 37,000 per year to 17,000 per year in 2051.
Around 90% of overseas migrants to Victoria are expected to settle in Melbourne, making NOM the main driver of Melbourne’s population growth. Melbourne is also expected to retain strong natural increases throughout the projection period.
In contrast, the main driver of growth in regional Victoria will be migration from Melbourne. It is projected that population ageing and the increasing numbers of deaths in regional Victoria will result in a period of natural decrease in regional Victoria from the mid-2030s.
Over the next two decades, the seven designated Growth Area municipalities are expected to experience the greatest population growth, both in terms of the rate of growth and the quantity of increase. Figures 1 to 4 below show the projected increases and rates of growth for Local Government Areas (LGAs) from 2011 to 2031.
Population growth in four of the Growth Area municipalities (Wyndham, Casey, Whittlesea and Melton) is expected to exceed 100,000 persons per LGA from 2011 to 2031. Relatively high growth is also projected for the City of Melbourne and three of the key regional centres; Geelong, Ballarat and Bendigo.
In terms of the rate of growth (which is influenced by the size of the starting base population), the Shire of Mitchell is expected to nearly triple in population from 2011 to 2031, with a 172% increase on the 2011 base population. The southern part of the Shire of Mitchell was incorporated in the Urban Growth Boundary in 2010 and this will be a major factor in the municipality’s increasing rate of growth. In addition to the Growth Areas and central Melbourne, relatively high rates of growth are projected for the coastal areas of Bass Coast and Surf Coast, both of which are in peri-urban locations (adjacent to Melbourne and Geelong) and feature popular seaside and lifestyle attractors.Figure 1. Projected population change, 2011 to 2031, Local Government Areas
Figure 2. Projected population change, 2011 to 2031, Top 10 Local Government Areas
||Local Government Area
Projected population change (number of people)
Figure 3. Projected population growth rate, 2011 to 2031, Local Government Areas
Figure 4. Projected population growth rate 2011 to 2031, Top 10 Local Government Areas
||Local Government Area
Projected population growth rate (%)
Why will the number of households grow at a faster rate than population? Why is the average household size expected to decrease?
In Australia, a household is defined as either a person living alone or a group of people who live together in the same dwelling and who share resources such as food. Household growth is the result of the interaction of new household formation and existing household dissolution. New household formation and existing household dissolution can occur because of migration if all members of a household either immigrate or emigrate at the same time. New household formation also occurs when a person leaves the existing household to form a new household. This may occur, for example, when an adult child leaves the parental home to partner or live alone, or when a couple separates/divorces.
Thus, household growth is the interaction of not only natural increase and net migration, but also the way in which individuals form themselves into households, which is related to the age structure of the population, partnering and de-partnering trends, the age at which children leave the parental home, and broader socio-cultural trends. The relative faster growth of households compared with population is associated with a decline in the average household size.
The average household size is defined as the total number of persons living in private dwellings divided by the total number of households.
The continuing trend in decreasing fertility rates will lead to smaller and fewer families with children and larger numbers of couples without children. Furthermore, as older people are more likely to live alone (usually following the departure of their children from the family home and the death of one partner), the ageing of the population suggests a corresponding increase in the number of lone person households. This is likely to result in, on average, fewer people per household over time.
The average household size is a composite measure and results from the household formation decisions of people in each age group. Changes in the average household size are due to changes in the propensities (preferences) of each age group over their living arrangements and the relative size of each age group in the population.
Changes in household formation propensities over time are extremely difficult and problematic to model and, consequently, such changing patterns have not been integrated in the VIF 2012 projections model. Instead, the decreasing average household size projected in VIF 2012 is a result of the projected changes in the size and age structure of the population.
The major driver of changing patterns of population growth in Victoria relates to the large cohort of population born between 1945 and 1971 (aged 41 to 67 in 2012). The cohorts born after this ‘baby boom’ generation are smaller, due mainly to the decline in birth rates from 1971.
While the population has grown in size, the proportion of children in the population has steadily decreased. At the same time average life expectancy has risen due to improvements in medical science and the quality of health care, and generally healthier lifestyles.
These improvements are contributing to an ageing population in which the average age of the population is increasing. Victoria’s population is still growing in size through births and migration, but people aged 60 years and over are comprising a larger proportion of the total population.
Like the whole of Victoria, an older age profile is developing in Melbourne; however the overall age profile in Melbourne will remain younger on average than in regional Victoria. This is driven largely by the influx of younger migrants, mainly from other countries and from regional Victoria.
The full set of VIF 2011 products is available on the DPCD’s Victoria in Future website.
For further information or assistance about VIF 2011, please contact the DPCD Spatial Analysis and Research Branch.