Overview of Victoria in Future 2016 (VIF 2016)
VIF2016 refers to the updated population and household projections Victoria in Future 2016 produced by the Department of Environment, Land, Water and Planning.
VIF2015 and VIF2014 refers to the previous population and household projections Victoria in Future 2015 and Victoria in Future 2014 superseded by VIF2016.
Greater Melbourne refers to the Melbourne Greater Capital City Statistical area as defined by the Australian Bureau of Statistics (ABS). Victoria's Regions refers to the remaining 8 Statistical Areas Level 4 (SA4) either as individual regions or in total: Ballarat; Bendigo; Geelong; Hume; Latrobe – Gippsland; North West; Shepparton;Warrnambool and South West. Maps of these areas are available on the ABS web site www.abs.gov.au
Metropolitan Melbourne in VIF2016 refers to the region covered by the 31 local government areas of Melbourne. In Plan Melbourne, it also includes the growth areas of Wallan, Beveridge and surrounds. Regional Victoria refers to the region covered by the 48 local government areas and unincorporated areas outside of Melbourne. Maps of these areas are available on the ABS web site www.abs.gov.au
The year reference (e.g. 2011, 2031, 2051, etc) refers to the population at 30 June in that year.
For definitions of demographic terms, refer to the Glossary.
What is Victoria in Future 2016?
Victoria in Future (or VIF) is the official state government projection of population and households across Victoria. The Forward Policy and Research Branch of the Department of Environment, Land, Water & Planning produces the projections.
VIF2016 was released in 2016 and is the most up to date set of projections. The projections use the Estimated Resident Population (ERP) at 30 June 2015 as the base population. Data from 2011 to 2015 uses ERP while 2016 is the first year of the projected numbers. VIF2016 supersedes VIF2015 which was based on the population estimates as at 30 June 2014.
What is the purpose of VIF 2016 and who uses it?
VIF2016 projections show changes in population and households, in terms of number and characteristics (i.e. age structure, household types, location).
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.
VIF projections are an important guide for planning and building for our future. 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 supply.
Clause 11.02 of the State Planning Policy Framework explicitly requires planning for urban growth to have consideration to Victorian Government population projections.
What VIF 2016 products and data are available?
All VIF2016 products and data can be accessed via the Victoria in Future 2016 pages on the website of the Department of Environment, Land, Water and Planning (DELWP).
The VIF2016 Brochure is available in electronic format and hard copy. Hard copies can be requested from Forward Policy and Research.
- VIF2016 brochure: Summary of VIF2016 highlights, graphs, maps and data
- One-page Profiles: Summaries of VIF2016 data and graphs for Victoria and each of the Local Government Areas
- Data Files: Excel spreadsheets of detailed VIF2016 data (refer to table below)
VIF2016 Data Files
Individual years from 2011 to 2051
Greater Melbourne and
SA4s in Victoria's regions
Every fifth year from 2011 to 2051
Local Government Areas
Individual years from 2011 to 2031
Local Government Areas
Every fifth year from 2011 to 2031
VIF Small Areas
Individual years from 2011 to 2031
VIF Small Areas
Every fifth year from 2011 to 2031
Which geographical areas are not included in VIF2016?
VIF2016 does not provide projections for the following geographical areas:
- Other states/territories
- Suburbs and towns
- Postcode areas
The Australian Bureau of Statistics (ABS) produces population projections for Australia and other states/territories. These projections are available at the ABS website. 3222.0 - Population Projections, Australia, 2014 (base) to 2101.
When will VIF 2016 be updated?
VIF2016 was produced to take account of the results of the 2011 national Census and incorporates ABS population data as at 30 June 2016. The VIF2015 projections will be tested yearly against new published data when it becomes available, and a new Victoria in Future prepared.
Are these targets for future population and households?
VIF2016 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 policy measures that explicitly affect the sizes and distributions of future populations. They do not consider policies that may be introduced in the future.
VIF 2016 and other projections and demographic data
How do the VIF projections differ from other population projections?
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.
One key difference of methodology relates to migration within Australia. VIF2016 models the migration flows between Victoria and the other States, and between the regions of Victoria, while the ABS models the flows between the Greater Capital Cities and Rest of State areas across Australia.
Further differences result from VIF2016 and the ABS choosing different assumptions for the key drivers of population change: fertility and mortality rates and level of overseas migration. VIF2016 assumptions are detailed in another question.
VIF2016 projections are more detailed geographically than the ABS. The smallest areas in the ABS projections are the Capital City and Rest of State statistical areas. VIF2016 provides projections of population and households for Victoria, Greater Melbourne and the 8 SA4s in Victoria's Regions, and the 79 Local Government Areas (LGA) in Victoria. Following the development of the ABS new statistical geography (ASGS), Local Government boundaries and the ABS classification do not align completely. However, they both cover the whole of Victoria.
VIF2016 projections are also presented for a set of small areas specifically designed by DELWP to provide more local information than the LGAs. These Victoria in Future Small Areas (VIFSA) fit within the LGAs and cover the whole of Victoria.
The projections at sub-state geographies add up to the larger total. This is the case for the population projections and the household projections, as well as their components (age, sex, births, deaths, net migration and household types).
For the smaller geographical areas, DELWP gathers and analyses information about local land supply and patterns of residential development as a significant input to the VIF2016 projections to ensure that the VIF projections are realistic and take into account local influences on population change.
VIF2016 is independent of other projections of populations, prepared for example by local governments or private businesses.
How do the VIF 2015 projections compare with VIF2014 projections?
VIF2016 updates VIF2015 and broadly uses the same methodology but with slightly different assumptions. These assumptions are detailed in a separate question. VIF2016 produces results similar to VIF2015 at the broad scale. The differences are due to updated base populations and recent data on components of change, development rates and future land and dwelling supply.
The projected population for Victoria at 2051 has increased from 10.0 million in VIF2015 to 10.1 million in VIF2016. The projected population for Greater Melbourne at 2051 has increased from 7.8 million to 8.0 million, while the projection for Victoria's regions has decreased from 2.2 million to 2.1 million.
These projections are similar in scale to VIF2014. They represent a significant increase over projections from 2012 (8.7 million for Victoria in 2051). Due to large increases in actual and expected levels of overseas migration, most projections increased over this period. For example ABS's medium level projection in 2008 was for Australia's population to reach 34.2 million by 2051. ABS's medium level projection for Australia in 2051 was raised to 38 million in its 2013 projections.
How do population projections differ from the Estimated Resident Population?
The Estimated Resident Population (ERP) is the official measure of the population and is used as the base (starting) population for projections. The ERP is based on the concept of usual residence and is usually calculated after the reference period. The ERP for 30 June 2015 was first published in December 2015, and updated quarterly. The base ERP for Victoria used in VIF2016 was published by the ABS in June 2016.
The ERP is based on the count from the latest Census, with the addition of quarterly components of population growth (births, deaths, population movements). It incorporates the estimated Census net undercount (to account for people who were missed from or counted more than once in the Census), and is adjusted to include usual residents who were temporarily overseas at the time of the Census but had returned by the end of the reference period, 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 and for local government areas (ABS cat. no. 3301.0, 3218.0 and 3235.0).
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.
DELWP recommends that researchers wanting population data for a period covered by ERP data should use that source. 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 Australian Demographic Statistics, catalogue number 3101.0, available at the ABS website.
VIF 2016 methodology and assumptions
How are the VIF 2016 and 2016 projections of population and households developed?
The projections are developed by applying mathematical models using a known base (starting) population and assumptions about future change and distribution. The projections are not simply an extrapolation of existing trends or growth rates, rather they involve the application of specific assumptions developed from detailed analysis of data on fertility, mortality and migration.
At the local level they also take account of land availability and redevelopment potential, which influence the capacity of areas to provide new dwellings to house the growing population. Combined with the expected behaviour of existing populations, this has a strong influence on the spatial distribution of future population.
The DELWP modelling process involves both top-down and bottom-up modelling approaches. Top-down demographic models at the state and regional level determine the future population by age and sex for these areas. For local areas within these regions a combination of bottom-up models produces dwelling and household distributions which govern the final distribution of population. Likely dwelling construction and area capacities are developed from a range of DELWP, ABS and other sources including but not limited to building approvals, the Urban Development Program, DELWP's Housing Development Data, land use zoning and growth strategies. Top-down and bottom-up models are balanced to ensure all local totals sum to the state and regional totals.
The VIF2016 population and household projections draw on three standard forms of modelling:
- The Cohort Component model projects the population by age and sex for each period using the basic demographic equation:
Population at end of period = Base population + Births – Deaths + Net migration
- The Housing Unit model projects the supply of dwellings available for occupation in a given area for each period using the basic equation:
Occupied dwellings at end of period =
(Base stock of dwellings + new construction – demolitions)
* (occupancy rate).
Using an average number of persons expected in each household, the housing unit model can also be used to determine the total projected population for each area.
- The Household Formation model allocates the population into households, based on living arrangement propensities (i.e. the distribution of people of each age and sex across household types).
The whole projection process can be summarised as follows:
Step 1 - The Cohort Component model is used to determine the population by age and sex for Victoria.
Step 2 – The Cohort Component model is used to determine the population by age and sex for Greater Melbourne and the eight SA4 regions in the rest of the state.
Step 3 - The Household Formation model determines an initial control total of households in each region.
Step 4 – Expected dwelling construction from a number of project streams are brought together to determine total expected dwelling construction per area. (The four project streams are: broadhectare development; major redevelopment sites; major urban renewal precincts; dispersed infill development.)
Step 5 - The Housing Unit model uses the projected dwellings by small geographical area and by applying an expected average household size infers the total population in each small area.
Step 6 - The Cohort Component model is used in reverse to infer the age/sex distribution of each small area population.
Step 7 - The Household Formation model determines the number of households of each type in each small area.
Steps 8-10 – The models from steps 5 to 7 are iterated at least once more to ensure household and dwelling totals balance at each stage.
The Cohort Component model 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, interstate, regional migration total flows (in and out)
- overseas, interstate and/or regional migration age and sex distribution
The inputs for the Housing Unit model are:
- base year's stock of structural private dwellings
- new dwelling construction
- stock loss rates (through demolition or conversion to other uses)
- occupancy/vacancy rates (dwellings without usual resident households)
The Household Formation model, developed by McDonald and Kippen in 1998, has been adapted by DELWP to project household formation in Victoria. It applies a propensity (likelihood) to persons of each age and sex to live in each household type (including non-private households), and thus determines the number of households and average household size.
The living arrangement tables by age and sex from the 2011 Census provide the propensities used as input. The household types include:
- Couple with children
- Couple without children
- Lone parent family
- Other families of related persons
- Lone person household
- Group household
- Other household
Persons in non-private households are classified and projected separately.
Why does DELWP produce only one set of projections?
VIF2016 provides a single set of projections to allow analysis and decision making on a consistent base for all users.
DELWP performs sensitivity analyses on the main assumptions, before choosing the most reasonable single set and using it to produce one set of projections. This information is strengthened by extensive research on local and regional trends, and by wide consultations with people with specialist and local knowledge.
Using VIF2016 as reference, it is possible to analyse the effects of different policy scenarios on population levels, distribution between and within the regions of Victoria.
What are the main assumptions in VIF 2016?
The VIF2016 projections use the Estimated Resident Population for 30 June 2015 as the base population, the ABS Australian Demographic Statistics, cat 3101.0, published December 2015.
Components of population change
Populations grow (or decline) in number from a combination of 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 constitutes the basic demographic equation:
Change in population = births – deaths + net overseas migration + net internal migration
For each of the four components of population change, one main assumption has been developed at the state level.
State-level assumptions applied in VIF2016
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 and fertility rates
The assumed TFR is derived from assumptions about the fertility of women of individual ages between aged 15 and 49. The combined effect of these assumptions is to hold TFR constant at 1.8 for Victoria across the projection period.
Age-Specific Death Rate (ASDR) – the probability of a person dying during the following year, according to his/her age and sex
Gradual increase in age-specific life expectancy at birth to 88 for males and 90 for females by 2051.
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
In the short term VIF2016 relies on Commonwealth Government forecasts of arrivals and departures to Australia and allocates a share to Victoria based on recent trends. This results in NOM to Victoria increasing from approximately 57,000 in 2015-16 to 66,000 by 2019-20. VIF2016 assumes NOM remains within this range over the period to 2030, before increasing in line with the population to a level of approximately 75,000 in 2050-51.
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
At the start of the projection period VIF2016's assumptions reflect current strong NIM. However, NIM is expected to provide a small positive contribution to Victoria's population growth throughout most of the projection period. NIM reduces from +11,500 in 2015-16 to a long-term assumption of +2,000 from 2021-22.
For sub-state projections, local fertility rates and migration patterns are specified. The assumption for mortality is the same across all areas.
In VIF2016, the number of births each year is obtained by applying age specific fertility rates (ASFR) to the number of women in the relevant ages. These ASFRs represent the likelihood of a woman of a given age having a child within the year. Influences on fertility are complex and interact to varying degrees over time. It is difficult to measure the impact of any one influence. Nonetheless, recent trends have been fairly consistent, with declining rates for the youngest ages and increasing rates for the 30 to 39 year olds. VIF2016 assumes a continuation of these trends, within reasonable limits. Overall, the resulting Total Fertility Rate (TFR) remains fairly constant around 1.8 child per woman for the projection period.
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. After declining sharply in the early 1970's, the number of births has averaged around 61,000 per annum between 1975 and 2000. The number of births each year grew to 76,500 in 2013-14 and is expected to reach 117,000 by 2051.
There are 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. VIF2016 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 (e.g. 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 2051 is expected to have increased to 88 years for males and 90 years for females.
The Age-Specific Death Rates (ASDR) used in VIF2016 are slightly different to the 'medium' life expectancy assumption used by the ABS in its projections. VIF2016 assumes that people aged 60 to 90 have a slightly lower death rates compared to the ABS's assumption. After the age of 90, VIF2016 assumes higher death rates than the ABS's medium level assumption. The difference is due to recently published deaths data and advice obtained from demographic experts at the University of Queensland. While there are regional variations in mortality rates, the data are too volatile to exhibit useable trends. Hence, regional differences in ASDRs have not been incorporated in the VIF2016 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.
Net overseas migration
Net overseas migration (NOM) is the difference between people coming to live in Australia and residents leaving to settle overseas.
In the past, natural increase has generally contributed more to Australia's annual population growth than has overseas migration. However, since 2004-05, overseas migration has overtaken natural increase as the major contributor to population growth. In 2014-15, NOM accounted for 54% of the annual population growth of Victoria (ABS cat. no. 3101.0).
It is important to note that NOM is not the same concept as permanent migration. To be counted in the resident population, thus potentially in the NOM, a person has to live in Australia for at least 12 of the past 16 months, regardless of nationality, citizenship or legal status. In recent years, the largest contribution to NOM has been from people on temporary visas. In 2014-15, this group accounted for over 50% of Australia's NOM. Temporary visa holders include students, tourists, working holiday makers and subclass 457s.
In preparing the VIF2016 projections, the NOM assumption for Australia has been broken down into three periods:
- For the short term (to 2018-19), VIF2016 uses forecasts of net overseas migration made by the Department of Immigration and Border Protection (DIBP). These forecasts are based on existing visa applications and recent take-up rates. They suggest that NOM to Australia should rise to around 260,000.
- From 2018-19 to 2029-30, NOM is assumed to remain reasonably consistent with the later years of the DIBP short-term forecasts, therefore staying within a range from 240,000 to 260,000 per annum.
- After 2029-30, it is assumed that NOM remains around its long term average of around 0.8% of the population, which leads to gradual increases over time, reaching around 290,000 in 2051.
While the overall level of migration to Australia is indicative of prevailing conditions, it is the level of net overseas migration to Victoria which influences the state population. Victoria's share of overseas migration to Australia is currently tracking above its long term average of 25% per annum. VF2016 assumes Victoria's share of NOM will return from current high levels (29% is assumed for 2015-16) to approximately 26% for the life of the projections. According to the last Census, over 90% of overseas migrants to Victoria settled in Melbourne.
Overseas migration can vary greatly from year to year. The variations can be affected by economic conditions in Australia and overseas, with areas of strong economic growth and prosperity attracting higher levels of migration. The overseas migration assumption used in these projections should be seen as a long term annual average, rather than a prediction that overseas migration will be at a particular level in a particular year.
In discussing net overseas migration, it needs to be borne in mind that governments have much less control over migration than may be expected. State Governments have no control and can only influence Commonwealth Government through advocacy. In turn, Commonwealth Governments have chosen not to practice rigorous controls over the number of people moving in or out of the country. Numbers of permanent humanitarian and skilled migrants are capped by Commonwealth Government policy. On the other hand, Australian residents, and New Zealanders, come and go without restrictions. The numbers of long term but temporary migrants, such as students, working holiday makers and category 457 migrants, are not capped, nor are those coming under family reunion schemes.
Net interstate migration
Net interstate migration (NIM) between Victoria and the other States and territories has been a small component of population change since the 1990s. Movements in and out of Victoria have been in the order of 65,000-75,000 per annum over the last few years, with a net positive balance of peaking at over 10,000 in 2014-15.
After allowing in the short-term for current high levels, VIF2016 assumes that NIM will contribute 2,000 per annum to the Victorian population for most of the projection period. As the age structures of exiting and entering interstate migrants are not significantly different, a small positive NIM is not expected to have a marked effect on the projected population beyond its simple additive contribution.
How are local conditions taken into account in the projections?
DELWP takes into account local conditions and differences in developing the VIF2016 projections.
Locally specific fertility rates, overseas, interstate and local migration patterns are used in VIF2016. Because the numbers are too small to be reliable, mortality rates at local level cannot be used and common mortality rates are applied to all regions.
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 Department's Urban Development Program (UDP) provides updated analysis on the supply of and demand for residential and industrial land across the metropolitan Melbourne, Geelong and other regional centres over the short to medium term. In developing the VIF projections, DELWP takes into consideration the UDP information as well as information gathered through consultations with local governments, property and development experts and other stakeholders who have localised knowledge. For Melbourne LGAs, Housing Development Data which monitors the size and location of infill developments in residential areas is used to develop the extent of future dwelling additions.
Are residents in non-private dwellings included in the projections?
The numbers and characteristics of people living in non-private dwellings are explicitly accounted for in the household formation component of the VIF2016 projections, before the rest of the population is allocated to households.
In producing the projections for small areas, 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?
The ABS population counts and the VIF projections include all people who are considered to be 'usual residents' regardless of nationality, citizenship or legal status. A person is regarded as a usual resident if they have been (or expected to be) residing in Australia for a period of 12 months or more over a 16 month period, with the exception of foreign diplomatic personnel and their families. This 12 month period does not have to be continuous, to make allowance for brief stays overseas, which can be a common pattern for some long-stay migrant groups such as overseas students, business migrants and temporary employer-sponsored workers as well as Australian travellers.
How do the projections account for 'temporary' populations, such as those in popular holiday areas?
The VIF2016 projections are based on the estimated resident population as at 30 June and not on seasonal, temporary fluctuations. People are counted at their place of usual residence.
Places with large 'temporary' populations, like holiday destinations or farming areas with very seasonal activities, often have 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.
These low occupancy rates (or high vacancy rates) are recognised in the Housing Unit model part of the projection process.
VIF2016 provides a table of projected occupancy rates for all Local Government Areas from 2011 to 2031. LGAs which include significant temporary populations can be identified as those with especially low occupancy rates.
Users of VIF2016 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.
Commentary on key issues
What is driving projected population growth in Victoria?
Over the projection period net migration is expected to account for 60% of the projected growth and natural increase for the remaining 40%.
Net overseas migration to Australia is expected to increase from its current level of 200,000 to around 260,000 per annum in the short term to 290,000 by 2051. Victoria traditionally receives around 25% of the Australian NOM, though in recent years the share has been higher. In 2015-16 this projected to be around 57,000 persons and is expected to be about 75,000 persons by 2051.
The number of births per annum in Victoria is projected to increase from 77,000 in 2015-16 to 117,000 in 2051. The number of deaths is also expected to increase, from 38,000 in 2015-16 to 69,000 in 2051. Thus, natural increase is projected to increase from 39,000 per year to 48,000 per year in 2051.
The population of Melbourne will increase strongly through NOM, as over 90% of overseas migrants to Victoria are expected to settle there. But Melbourne is also expected to retain strong natural increase 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 lower levels of natural increase in regional Victoria.
Which Victorian areas will grow the most and why?
Within Greater Melbourne, the areas expected to increase the most are those with the greatest capacity for dwelling growth, namely the outer Growth Areas and the inner city. While the middle suburbs are expected to regenerate and increase steadily in population, the designated Growth Areas (49 per cent) and the five inner LGAs (16 per cent) are expected to account for around two thirds of population growth to 2031.
In Victoria's regions the largest numbers of projected extra dwellings, and thus largest concentrations of population growth, are in the major regional cities and the areas close to Melbourne. Between 2011 and 2031, the three largest LGAs (Greater Geelong, Greater Bendigo and Ballarat) are projected to account for around half of the population growth in Victoria's regions.
Top five local government areas, largest and fastest growth 2011 to 2031
Metropolitan largest growth
Regional largest growth
Metropolitan fastest growth
Regional fastest growth
Greater Geelong (81,000)
Greater Bendigo (43,000)
Baw Baw (2.3%)
Golden Plains (2.1%)
Baw Baw (24,000)
Surf Coast (2.0%)
Maps showing projected changes, in numbers and average annual rates, for LGAs in Victoria between 2011 and 2031 are published in the VIF2016 brochure.
Why will the number of households grow at a faster rate than population? Why is the average household size expected to decrease?
A household is defined as one or more persons, at least one of whom is at least 15 years of age, usually resident in the same private dwelling. The number of households changes when complete households move in or out of an area because of migration. 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. Households also disappear when people previously living separately move in together, or when people move into non-private accommodation.
Thus, household number growth is function not only of the size of the population, 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 a range of socio-cultural factors.
Over the last twenty years, the average household size in Victoria has decreased, and household numbers have increased faster than the total population.
This is the results of several factors:
- an increase in the proportion of the population in the older age groups, which traditionally have the highest propensity to live in small households (alone or in couple without children);
- an increase in the propensity for persons of most ages to live alone, and
- a decrease in the proportion of children and an increase in the number of sole parent families, resulting in smaller families with children.
Changes in household formation propensities over time are extremely difficult to measure and problematic to model. Consequently, such changing patterns have not been integrated in the VIF2016 projections model. Nonetheless, the projected changes in the population age structure result in a further decrease of the average household size.VIF2016 projects that average household size will decrease from 2.53 in 2011 to 2.41 by 2051.
Why is the population ageing?
The Australian population is said to be ageing because the proportion of people in the older age groups is increasing. This change in the age structure reflects two separate phenomena.
Firstly, life expectancy at all ages, especially the older ages, has risen, due to improvements in medical science and the quality of health care, and generally healthier diets and lifestyles. This increases the average age of the population.
Secondly, over the coming years, the 'baby boomer' cohort will reach the age of 65 and become 'old'. This cohort is large in Australia. It was boosted by the large number of births as a result of high fertility rates and large number of young adult migrants in the 1950's and 1960s.
However, over the projection period, the increase in births will increase the number of young people in the population, therefore slowing the rate of ageing.