4102.0 - Australian Social Trends, April 2013  
ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 10/04/2013   
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The 'average' Australian

This article features in Episode 12 of the Australian Social Trends Podcast series.
Listen to the episode, or subscribe to the series, here AST Podcast via RSS, or via iTunes.


SEX RATIO(a), AUSTRALIA - 1911 to 2011 (b) (c)

Line graph of sex ratio in Australia – 1911 to 2011
(a) Number of males per 100 females.
(b) Data for 2011 is preliminary and subject to revision.
(c) Data for 1911 is the Census count, data for 1921 to 1970 are population estimates. Data from 1971 onwards are estimates of the resident population. Data for 1912-1920 has been linearly interpolated.
Source: Australian Historical Population Statistics, 2008 (cat. no. 3105.0.65.001), Australian Demographic Statistics, June 2012 (cat. no. 3101.0)

Related terms:
average Australian, typical Australian, Census, religion, country of birth, language, education, diversity, demographics.



INTRODUCTION

Australia is a large and diverse country, and every five years, the Census aims to visit each and every dwelling across Australia, collecting information from each and every person. The Census shows that Australians come from more than 200 countries, speak over 300 languages at home, belong to more than 100 different religious groups, and work in more than 1000 different occupations.

However, despite the considerable diversity in Australia and the changes Australia has gone through over the years, the largest groups of Australians have actually changed remarkably little.

As well as looking at the characteristics of the average or "typical" Australian, this article also explores Australia's underlying diversity by looking at particular groups or particular places that might be quite different from the average. This article also looks at some of the major changes in Australian society over the years, to shed light on how Australia is changing and how it might look in the future.

WHO IS THE AVERAGE AUSTRALIAN?

Are they a man or a woman?

Despite many people's image of the typical Australian being male, the average Australian is in fact a woman: in 2011, just over half of all people in Australia were female.

Throughout most of the twentieth century, there were more men than women in Australia, but since 1979, women have slightly outnumbered men. In 1911, there were around 108 men for every 100 women, but in recent years, the sex ratio has remained relatively constant at around 99 men for every 100 women.

Some places in Australia also have quite uneven numbers of men and women. For example, Kirkconnell in NSW (home to a minimum security prison), had 183 men and no women, and Edinburgh in SA (home to a Royal Australian Air Force base), had 186 men and 7 women. Conversely, Lawes in Qld (home to a women's prison) had 226 women and 79 men.

Excluding areas with large numbers of people living in non-private dwellings such as prisons and military bases, suburbs that had many more men than women in 2011 included Darlinghurst and Surry Hills in Sydney. These suburbs were home to large numbers of male same-sex couples. However, most of the places with more men than women were mining towns, such as Newman and Tom Price in Western Australia. Suburbs that had many more women than men included Mosman in NSW and Mornington in Victoria.

How old is the average Australian?

In 2011, the average Australian was 37 years old.

The median age increased from 1911 until the baby boom after World War II, when the median age began to fall, going from 30 years for men and 31 years for women in 1946 to 27 years for men and 28 years for women in 1971. However since 1971, the median age has been steadily increasing, to now stand at 36 years for men and 38 years for women. Due to the longer life expectancy of females, the median age for women is slightly older than that of men.

MEDIAN AGE IN YEARS, AUSTRALIA - 1911 to 2011 (a) (b)
Line graph of median age in years of men and women in Australia – 1911 to 2011
(a) Data for 2011 is preliminary and subject to revision.
(b) Data for 1911 is the Census count, data for 1921 to 1970 are population estimates. Data from 1971 onwards are estimates of the resident population. Data for 1912-1920 has been linearly interpolated.
Source: Australian Historical Population Statistics, 2008 (cat. no. 3105.0.65.001), Australian Demographic Statistics, June 2012 (cat. no. 3101.0)

In some parts of Australia the median age is quite different to the Australian average.

Many of the areas with high median ages in 2011 were small coastal communities popular with retirees, such as West Haven and Laurieton on the mid-North Coast of NSW, Sorrento in Victoria, Bongaree on Bribie Island in Queensland, and Goolwa and Encounter Bay in South Australia. These communities all had a median age over 60.

One of the communities in Australia with the youngest median age is Claymore in South-Western Sydney, where the median age was just 20. In 2011, Claymore was home to a large number of children, many in one parent families.

CULTURAL DIVERSITY

Where were they born?

In 2011, only 3% of Australians reported they were Aboriginal or Torres Strait Islander. Of these, the majority were Aboriginal only (90%), 6% were Torres Strait Islander only, and 4% were both Aboriginal and Torres Strait Islander.

Despite Australia's cultural diversity and long history of immigration, the average Australian was born in Australia, and so were both of their parents. In 2011, nearly three quarters of people (74%) were born in Australia, and more than half (54%) had both their parents born in Australia.

In 1911, 83% of people were born in Australia and this increased at every Census until the 1947 Census (90%). After this point, with the increase in immigration following the end of World War II, the proportion of people born in Australia has steadily fallen.

PROPORTION BORN IN AUSTRALIA(a) -1911 to 2011
Line graph of proportion born in Australia – 1911 to 2011
(a) Data has been linearly interpolated for non-Census years.
Source: Censuses of Population and Housing, 1911 to 2011, Australian Historical Population Statistics, 2008 (cat. no. 3105.0.65.001)

The proportion of people that were born in Australia is far from uniform across Australia, with some areas having a higher proportion of people born overseas. In the five mainland state capitals, 34% of people were born overseas, while in rural areas and towns of under 10,000 people, only 12% of people were born overseas.

As might be expected, the places with the lowest proportion of people born overseas were mainly Aboriginal and Torres Strait Islander communities. In the capital cities, the suburbs with the lowest proportion of people born overseas were all in Hobart: Gagebrook (2%), Herdmans Cove (2%), and Honeywood (3%).

Suburbs with a much higher than average proportion of people born overseas included Haymarket (88%) and Sydney (78%) in New South Wales, home to large proportions of people born in China, Indonesia, and Thailand; and Harris Park (76%), which is home to a large India-born community (43% of those living in Harris Park were born in India). The India-born population of Harris Park has grown quite quickly: ten years earlier in 2001, only 16% of the population was born in India.

In Melbourne, Clayton (70%) and Springvale (69%) in the south-eastern suburbs also had a much higher than average proportion of people born overseas. Clayton, home to Monash University, has a large number of people born in China, India, and Malaysia (the majority of whom are students), while Springvale has a large Vietnamese community. Nearly one in four people living in Springvale (22%) were born in Vietnam.

While the overall proportion of people born overseas is increasing relatively slowly, particular groups have shown substantial increases in recent years. The largest numerical increases between 2001 and 2011 came from India (increasing from 95,000 in 2001 to 295,000 in 2011), and China (increasing from 143,000 in 2001 to 319,000 in 2011).

The largest single group of people born overseas continues to be those born in the United Kingdom, making up 5% of Australia's population and 21% of all overseas born living in Australia. However amongst recent arrivals (people that arrived in Australia after 2006) the top position is held by India. People born in the UK made up 12% of recent arrivals, while people born in India made up 13%.

One of the fastest growing groups in recent years has been people born in Nepal. In 2011 there were 24,600 people born in Nepal, up from just 2,600 in 2001 and 4,600 in 2006 - a five-fold increase in just five years.

Although still only making up a very small proportion of overseas born people in Australia, many of the other fastest growing groups between 2001 and 2011 were from African nations such as Sudan, Liberia, Burundi and the Democratic Republic of Congo. In 2011, there were 22,900 people living in Australia that were born in Sudan or South Sudan, up from 4,900 in 2001.

What is their ethnic background?

The Census collects information on ancestry, which allows us to look at people's cultural and ethnic background, which may be different to their country of birth.

Australians come from a large number of different cultural and ethnic groups. However, the most commonly reported ancestry was English (36%), ahead of Australian (35%), Irish (10%) and Scottish (9%). All together, nearly three-quarters of Australians had at least one of these ancestries (people can report more than one ancestry).

More people are identifying themselves as having "Australian" ancestry. In 1986 when ancestry was first asked in the Census, 23% of people reported Australian ancestry, compared with 35% in 2011.

What language do they speak?

The average Australian only speaks English at home. In 2011, 81% of people reported only speaking English at home, down slightly from 86% in 1986. Nevertheless, in 2011, nearly one in five people spoke a language other than English at home.

The most common language other than English spoken at home in Australia is now Mandarin, spoken by 1.6% of people. The number of Mandarin speakers has grown significantly in recent years, from under 200,000 in 2001 to 336,000 in 2011, taking top spot from Italian. This is mainly related to increased migration from China: most people who spoke Mandarin at home were born in China (63%), though there were also relatively large numbers of Mandarin-speakers born in Australia (13%), Malaysia (8%), Taiwan (7%) and Singapore (4%).

Another Chinese language, Cantonese (1.3%) is also among the most commonly spoken languages in Australia other than English.

Other commonly spoken languages other than English include Italian (spoken by 1.5% of people), Arabic (1.4%), Greek (1.2%), and Vietnamese (1.1%).

The most widely spoken languages other than English have changed significantly in recent years. In 1986 the most common languages other than English spoken at home were Italian and Greek, and there were nearly three times as many speakers of Italian as all Chinese languages combined. Since then however, the number of speakers of Italian and Greek has fallen as immigration from those countries has slowed, while the number of speakers of Chinese languages has more than quadrupled. The number of speakers of Arabic and Vietnamese have also increased substantially, though not to anywhere near the extent of Chinese languages.

NUMBER OF PEOPLE SPEAKING SELECTED LANGUAGES AT HOME - 1986 to 2011
Line graph of number of people speaking selected languages at home – 1986 to 2011
(a) Chinese languages include Cantonese, Hakka, Mandarin, Wu, Min Nan, other Chinese languages not elsewhere classified, and Chinese, not further defined.
Source: Censuses of Population and Housing, 1986 to 2011

What is their religion?

The average Australian belongs to a Christian religion.

While the majority of Australians continue to belong to a Christian religion, the proportion has fallen by more than a third, from 96% in 1911 to 61% in 2011.

PROPORTION OF PEOPLE AFFILIATED WITH A CHRISTIAN RELIGION(a) - 1911 to 2011
Line graph of proportion of people affiliated with a Christian religion – 1911 to 2011
(a) Data has been linearly interpolated for non-Census years.
Source: Censuses of Population and Housing, 1911 to 2011

The proportion of Australians reporting they were Catholics has remained relatively constant at around 25% since 1961, however the proportion of people reporting they were Anglicans has more than halved in that time, from 35% to 17%. At some point between the 1981 and the 1986 Census, Catholicism overtook Anglicanism as Australia's largest religious group.

PROPORTION OF PEOPLE AFFILIATED WITH SELECTED RELIGIONS (a) - 1911 to 2011
Line graph of proportion of people affiliated with selected religions – 1911 to 2011
(a) Data has been linearly interpolated for non-Census years.
Source: Censuses of Population and Housing, 1911 to 2011

Since 1971 the proportion of people with no religion has risen from under 7% to more than 22% of Australians. In the five years between the 2006 and 2011 Censuses it rose from 19% to 22%. The vast majority of people in this group just state "No religion", but this group also includes people who report they are Agnostic, Atheist, or Humanist.

Meanwhile, the number of adherents to non-Christian religions has grown significantly, from just 69,000 in 1961 (half a percent of the population) to 1,546,000 in 2011 (7%).

The composition of the non-Christian religions has changed significantly over the years. In 1961 by far the largest non-Christian religion was Judaism. While in 1961 Jews outnumbered all other non-Christian groups combined by more than six to one, by 2011 Judaism ranked a distant fourth behind Buddhism, Islam, and Hinduism, but ahead of Sikhism.

NUMBER OF PEOPLE AFFILIATED WITH SELECTED NON-CHRISTIAN RELIGIONS - 1961 to 2011
Line graph of number of people affiliated with selected non-Christian religions – 1961 to 2011
Source: Censuses of Population and Housing, 1961 to 2011

One of the parts of Australia with a much higher than average proportion of people expressing a religious affiliation was Home Island in the Cocos (Keeling) Islands (98%), which is mainly home to an ethnically Malay Islamic community. Other areas with a high proportion of people belonging to religious groups were mainly Aboriginal and Torres Strait Islander communities in Australia's north such as Wilora (between Alice Springs and Tennant Creek in NT), and Keriri Island in the Torres Strait (both over 95%). Many communities were formerly missions run by the different Christian churches, and this influence can be seen in the religions of many of the people living there.

Of the capital cities, Sydney had the highest proportion of people reporting a religion (75%). The suburbs of Mount Lewis (93%), Bossley Park (92%), Prairiewood (91%) and Abbotsbury (91%) had particularly high rates. People in Bossley Park, Prairiewood and Abbotsbury in the Fairfield area were predominantly Catholic (53%, 47% and 58%), while Mount Lewis in Bankstown was predominantly a mixture of Catholics (37%) and Muslims (24%).

Hobart had the highest proportion of people with no religion of any capital city (29.1%), just ahead of Canberra (28.9%).

For more on cultural diversity, see Reflecting a Nation: Cultural Diversity in Australia (cat. no. 2071.0).

WORK

The average man and the average woman are both in paid employment. According to the 2011 Census, 67% of men and 56% of women aged 15 and over were employed.

It is only relatively recently that the average woman has been in paid employment. According to the ABS Monthly Labour Force Survey, the proportion of women who were employed first passed 50% in June 1998.

PROPORTION EMPLOYED (a), PERSONS AGED 15 YEARS AND OVER, BY SEX - FEB 1978 to AUG 2011
Line graph of proportion employed, persons aged 15 years and over, by sex – Feb 1978 to Aug 2011
(a) Trend estimates.
Source: Labour Force, Australia, December 2012 (cat. no. 6202.0)

What do they do for a living?

For both men and women the most common occupation in Australia in 2011 was sales assistant, reflecting the large number of part-time sales assistants in the labour force. For men, other common occupations were truck driver, electrician, and retail manager; for women other common occupations were general clerk, primary school teacher, and office manager.

The most common occupations have changed significantly over the years. In 1911, the most common occupations for men were farmer and farm labourer, and house servant and clothing maker for women. In 1961, the most common occupations were clerks and truck/van drivers for men, and stenographers/typists and shop assistants for women.

How many hours do they work?

The average employed man tended to work longer hours than the average employed woman. For those who worked in the week prior to Census Night in 2011, men worked an average of 41 hours, compared with 32 hours for women.

While men worked more hours than women in paid employment, the situation was reversed when looking at unpaid domestic work. The average man did less than five hours of domestic work in the last week, while the average woman did five hours or more.

How do they get to work?

The average Australian takes a private car to work, usually as a driver.

The car continues to be by far the most popular way to get to work, with more than two-thirds of people using this mode of transport in 2011 (69%). This is more or less unchanged since the question was first included on the Census in 1976 (67%).

The average Australian household now has two or more cars. In the forty years between 1971 and 2011, the proportion of households with two or more motor vehicles has doubled, from 26% to 54%.

PROPORTION OF HOUSEHOLDS WITH TWO OR MORE MOTOR VEHICLES - 1971 to 2011
Line graph of proportion of households with two or more motor vehicles – 1971 to 2011
Source: Censuses of Population and Housing, 1971 to 2011

EDUCATION

Have they finished school?

The average Australian aged 15 years and over has finished Year 12: in 2011, 52% had completed Year 12 or equivalent. However, this proportion varies significantly by age, with older people much less likely to have finished Year 12. This reflects lower levels of Year 12 attainment when these people were younger.

PROPORTION OF PEOPLE WHO HAVE COMPLETED YEAR 12 OR EQUIVALENT, BY AGE - 2011
Line graph of people who have completed year 12 or equivalent, by age - 2011
Source: Census of Population and Housing, 2011

Do they have a qualification?

The average Australian aged 15 years and over has a non-school qualification. In 2011, just over half (56%) of people aged 15 and over had a non-school qualification, more than twice as many as in 1981 (26%).

PROPORTION OF PEOPLE AGED 15 YEARS AND OVER WITH A NON-SCHOOL QUALIFICATION - 1981 to 2011
Line graph of people aged 15 years and over with a non-school qualification – 1981 to 2011
Source: Censuses of Population and Housing, 1981 to 2011

In 2011, the most common highest level of qualification was a Certificate (40%), and the most common field of study was Business and Management (9%).

In some parts of Australia, there are much higher than average proportions of people with qualifications, or people with higher qualifications than the average. For example, in Canberra, 37% of people aged 15 years and over had a Bachelor degree or higher, the highest of any capital city.

FAMILIES

The average Australian adult (aged 18 years and over) is in a registered marriage. In 2011, over two-thirds of adults (69%) had been married at some point in their lives, and just over half (51%) were married at the time of the 2011 Census.

However, entering into a registered marriage has become less common over the years, and those who do enter into a marriage tend to do so later in life. For example in 2011, over three-quarters (79%) of 40 year old women had been married, but 20 years earlier in 1991, it was over 90%.

The average Australian lives in a couple family: in 2011, over two-thirds of people (71%) were living in a couple family. While the number of same sex couples has risen substantially in recent years, they still only make up less than 1% of all couples.

Most couple families have children living at home (54%), and amongst these families, the most common family size was four people, two adults and two children.

In families with two dependent children, most families (52%) had a girl and a boy, while 25% had two boys and 23% had two girls. The median age of the eldest child was nine, and the median age of the younger child was six.

WHERE DO THEY LIVE?

The average Australian lives in one of our state or territory capitals. In 2011, three out of every five people (60%) lived in a capital city, with slightly over a third (35%) living in either Sydney or Melbourne. Aside from the capital cities, other major cities are Gold Coast, Newcastle, Central Coast, Wollongong, Sunshine Coast, Townsville, Geelong and Cairns. Together, the capitals and other major cities accounted for over two-thirds (69%) of Australia's population in 2011.

Altogether, nearly 90% of Australians live in urban areas (cities or towns of more than 1,000 people), and another 3% live in smaller towns or localites. However, in 2011, 1.8 million people lived in rural areas outside any defined towns or localities - more people than live in Perth.

On average, according to the 2011 Census, there were 2.8 people per square kilometre in Australia, which is one of the lowest population densities in the world. However, since most of Australia's population is clustered in cities and towns, the majority of people live in areas where the population density is much higher than the average.

On average, Sydney has 1,900 persons per square kilometre, and Melbourne has 1,500. Darwin, the least densely populated Australian capital, has 480 persons per square kilometre.

Inner city areas tend to have the highest population density. For example, the Melbourne CBD has 8,500 persons per sq km. However, the most densely populated part of Australia is a small area just north of Central Railway Station in Sydney, between Pitt and Castlereagh Streets. This area has 1,960 people living in a land area of slightly over one hectare (or a bit over two and a half acres), equivalent to a population density of 186,000 persons per square kilometre.

What kind of house do they live in?

The average Australian lives in a separate (free-standing) house. This has not changed much over the years: in 2011, separate houses made up 74% of private dwellings, down only slightly from 77% twenty years earlier in 1991 and 78% twenty years before that in 1971.

The small change that has occurred is driven in part by increased construction of high rise units. High rise units (flats or apartments in four or more storey blocks) made up 4% of all dwellings in 2011, up from 2% in 1991. High rise living is more common for younger adults rather than older people or families with children (48% of people living in high rise units were aged 18 to 35 years, compared with 25% in the general population).

How many bedrooms does the average house have?

In 2011, the average private dwelling had three bedrooms.

The number of bedrooms varies according to the type of dwelling. While most high-rise units (82%) have two bedrooms or less, most separate houses have three bedrooms (50%), four bedrooms (32%), or more (7%).

There are a number of suburbs where the houses tend to be much larger than the Australian average. For example, in O'Malley in the ACT, 41% of dwellings had five or more bedrooms. Other suburbs with a high proportion of dwellings with five or more bedrooms include Denham Court (35%) and Middle Dural (34%) in Sydney, and Stretton (33%) and Chandler (32%) in Brisbane.

Do they own their own house?

In 2011, owning a dwelling with a mortgage was the most common tenure arrangement. Slightly more than a third (35%) of dwellings were owned with a mortgage, 33% were owned outright, and 29% were rented, with the remainder occupied under less common arrangements such as rent/buy schemes or occupied rent free.

While in 2011 owning a home with a mortgage was the most common tenure type, just ten years previously in 2001 it was less common than either owning a home outright or renting.

PROPORTION OF DWELLINGS WITH SELECTED TENURE TYPES - 2001 to 2011
Bar graph of dwellings with selected tenure types – 2001 to 2011
Source: Censuses of Population and Housing, 2001 to 2011

In 2011, the average Australian household with a mortgage paid $1800 a month in mortgage repayments, up from $1300 five years earlier.

Parts of Australia with a higher than average proportion of homes being purchased are mainly on the newly developed fringes of capital cities, including Botanic Ridge in the outer South-Eastern suburbs of Melbourne (85%), Piara Waters in the South Eastern suburbs of Perth (82%), The Ponds in North Western Sydney (81%), New Beith in Logan City (80%), and Honeywood in Hobart (78%).

How often do they move house?

The average Australian has lived at their current place of residence for at least five years. Nearly three in five people (58%) lived in their current place of residence five years ago, however the proportion varies significantly by age.

PROPORTION LIVED ELSEWHERE FIVE YEARS AGO, BY AGE AND SEX – 2011
Line graph of proportion lived elsewhere five years ago, by age and sex - 2011
Source: Census of Population and Housing, 2011

Nearly two-thirds of people in their twenties and thirties (64%) lived somewhere else five years ago. Older people were much less likely than younger people to have moved in the previous five years, though the proportion begins increasing later in life, as many older people move into nursing homes or retirement villages.

PROFILE OF THE AVERAGE AUSTRALIAN

According to the 2011 Census, the average Australian is a 37 year old woman, born in Australia and with both of her parents also born in Australia. She has English, Australian, Irish, or Scottish ancestry. She speaks only English at home and belongs to a Christian religion, most likely Catholic.

She is married, and lives with her husband and two children (a boy and a girl aged nine and six) in a separate house with three bedrooms and two cars in a suburb of one of Australia's capital cities. They have lived in that house for at least five years, and have a mortgage where they pay $1800 a month.

She has a Certificate in Business and Management, and drives to her job as a sales assistant, where she works 32 hours a week. She also does unpaid work around the house for five or more hours a week.

While many people will share a number of characteristics in common with this "average" Australian, out of the nearly 22 million people counted in Australia on Census Night, 9 August 2011, no single person met all these criteria.

While the description of the average Australian may sound quite typical, the fact that no-one meets all these criteria shows that the notion of the "average" masks considerable (and growing) diversity in Australia.

PROFILE OF THE AVERAGE AUSTRALIAN – 1911, 1961 and 2011

SELECTED CHARACTERISTICS OF THE AVERAGE AUSTRALIAN, 1911-2011

1911
1961
2011

Sex
Male
Male
Female
Age
24
29
37
Born
Australia
Australia
Australia
Job(a)
Farmer
Clerk
Sales Assistant
Religion
Anglican
Anglican
Catholic

(a) The job shown is the most common occupation for the sex of the average person in that year.
Source: Australian Historical Population Statistics, 2008 (cat. no. 3105.0.65.001), Australian Demographic Statistics, June 2012 (cat. no. 3101.0), Censuses of Population and Housing, 1911, 1961, and 2011

PROFILE OF THE AVERAGE AUSTRALIAN BY STATE AND TERRITORY

SELECTED CHARACTERISTICS OF THE AVERAGE AUSTRALIAN, 2011

NSW
Vic.
Qld
SA
WA
Tas.
NT
ACT

Sex
Female
Female
Female
Female
Male
Female
Male
Female
Age
37
37
36
39
36
40
31
34
Born
Australia
Australia
Australia
Australia
Australia
Australia
Australia
Australia
Job(a)
Sales Assistant
Sales Assistant
Sales Assistant
Sales Assistant
Truck Driver
Sales Assistant
Defence Force Member - Other Ranks
General Clerk

(a) The job shown is the most common occupation for the sex of the average person in that state or territory.
Source: Australian Demographic Statistics, June 2012 (cat. no. 3101.0), Census of Population and Housing, 2011

AVERAGE HEIGHT AND WEIGHT

The average Australian is now taller than in the past. In 2011-12, the average man was 175.6 cm tall (around 5 feet 9 inches), 0.8 cm taller than in 1995. The average woman was 161.8 cm tall (around 5 feet 4 inches), 0.4 cm taller than in 1995.

However, Australians have put on weight at an even faster rate. The average man weighed 85.9 kg, up 3.9 kg from 1995, and the average woman weighed 71.1 kg, up 4.1 kg.

This means that the average man and the average woman now both fall into the overweight category, as measured by the Body Mass Index (BMI).

Source: Australian Health Survey: First Results, 2011-12 (cat. no. 4364.0.55.001)

Data sources and definitions

Most of the data in this article comes from the Census of Population and Housing. Censuses were conducted in 1911, 1921, 1933, 1947, 1954, 1961, and every five years after that, with the most recent Census held on 9 August 2011. Where necessary due to the uneven time periods between Censuses, data has been linearly interpolated for non-Census years.

The "average" is a measure of the most typical value in a dataset, and can refer to a number of different statistical concepts: the mean, median or mode. The mean is the sum of the numbers divided by the number of observations, for example for weight, the weights of all persons are added together and divided by the number of persons. The median is the value that divides the dataset into two equal parts, for example for age, 37 is the median as half of people are aged less than 37, and half of people are aged over 37. The mode is the most commonly occurring value in a dataset. Since most Census data is categorical, the average used in this article is most commonly the mode - in most cases it was the category that accounted for the majority of Australians. For most continuous variables such as age or mortgage repayments, the median is used. However for hours worked, the mean is used.

Most data in the Census is applicable only to people that usually live in Australia and excludes overseas visitors. Overseas visitors are people that usually live overseas and will be in Australia less than one year. Percentages generally exclude "not stated" categories from the denominator, though as Religion is an optional question, proportions include the not stated category in the denominator.

The median age and sex ratio in this article is based on Estimated Resident Population (ERP). ERP is the official estimate of the population and is based on the Census count, adjusted for Census underenumeration, births, deaths, and net overseas migration. ERP has been available since 1971.

References to cities and towns are using the Urban Centre/Locality (UCL) classification, which is based on the continuously built up urban area of a town or city. References to suburbs or other areas are using the State Suburb (SSC) classification. This classification aligns closely to officially gazetted suburb and locality boundaries. The analysis of the most densely populated part of Australia uses Statistical Area 1s. For more information on these geographic classifications, see Australian Statistical Geography Standard (ASGS) (cat. no. 1270.0.55.001).

The information on housing tenure in the Census provides a snapshot of the nature of the occupancy of the dwelling stock in Australia on Census Night. The housing tenure of the dwelling where a household spent Census Night may differ from that of the dwelling where they usually live. For more information, see Fact Sheet: Housing Tenure in the Census.

A dependent child is a child aged less than 15 years, or a child who is 15-24 years of age and who attends a secondary or tertiary educational institution as a full-time student and for whom there is no identified partner or child of his or her own usually resident in the same household.

The data on proportion of people employed (also known as the employment to population ratio) is the trend estimate from the labour force survey. The trend series smooths the seasonally adjusted series to reduce the impact of irregular movements in the seasonally adjusted series. Seasonal adjustment is a means of removing the estimated effects of normal seasonal variation from the series so that the effects of other influences on the series can be more clearly recognised. For more information on these and other labour force data, see Labour Force, Australia (cat. no. 6202.0).

Body Mass Index (BMI) is a measure where the weight in kilograms is divided by the square of the height in metres. Values of less than 18.5 are considered underweight, 18.5 to less than 25 are considered normal, 25 to less than 30 are considered overweight, and values of 30 or more are considered obese.