> Source: https://www.k-stra.com/product/data/population/
> Updated: 2026-11-03

Data · Population

# Which population data does K-Stra use?

Who lives around an address is the first number of almost every analysis. Here is where each population figure comes from, and how old it is.

In short

K-Stra counts residents, males and females and fifteen age classes from the ABS population estimates at 30 June 2025, and takes families, birthplace, education and marital status from the 2021 Census. Both are spread onto address points, so a drive time adds up exactly the homes it reaches. Each council also has its population year by year since 2019.

[Count the residents of an area](https://www.k-stra.com/a/?src=product-data-population)

Variables

## Which population variables are there?

Thirteen variables in five topics of People & Economy: Residents, Postcodes, Age, Education and marital status, Population trend. Each topic costs 2 credits; the size of the area is free.

Population variables in K-Stra with source, reference period and level

Variable

Source

Reference period

Measured at

Residents, by travel-time band and by council

Residents

ABS population estimates

30 June 2025

Council total, spread onto addresses

Males and females

Residents

ABS population by age and sex

30 June 2025

Council, spread onto addresses

Families and residents per family

Residents

ABS Census 2021

Census 2021

SA1, spread onto addresses

Residents born overseas, also by postcode

Residents

ABS Census 2021

Census 2021

SA1, spread onto addresses

Dwellings and occupied dwellings

Residents

ABS Census 2021

Census 2021

SA1, spread onto addresses

Residents of each postcode inside the area, and the share of the postcode it covers

Postcodes

ABS population estimates

30 June 2025

Sum of the addresses

Age in 8 ten-year and 15 five-year classes, by sex

Age

ABS population by age and sex

30 June 2025

Council, spread onto addresses

Average age and old-age index

Age

ABS population by age and sex

30 June 2025

Derived from the age classes

Age groups: under 5, children 0–14, working age 15–64, 65 and over, 70 and over

Age

ABS population by age and sex

30 June 2025

Derived from the age classes

Highest qualification of residents aged 15 and over

Education and marital status

ABS Census 2021

Census 2021

SA1, spread onto addresses

Highest year of school completed

Education and marital status

ABS Census 2021

Census 2021

SA1, spread onto addresses

Marital status of residents aged 15 and over

Education and marital status

ABS Census 2021

Census 2021

SA1, spread onto addresses

Population of each council year by year, with the average yearly change

Population trend

ABS population estimates

2019 to 2025, at 30 June

Council only

Method

## How are population figures counted inside a drive time?

The ABS publishes population for areas, never for streets. K-Stra spreads it onto 14.5 million address points in two layers: the shape inside each council comes from the 2021 Census at its finest level, the SA1 area; the total comes from the council’s estimate at 30 June 2025.

Inside an SA1, people are shared among addresses in proportion to how many each building can house, judged from the road network and the size of the building. A drive time then adds up the addresses it reaches, so its edge passes between street numbers instead of halving a statistical area.

Because every level starts from the same council estimates, the levels agree: postcodes, suburbs, councils, states and Australia add up to the same 27.6 million residents. Census variables follow the same route and keep each council’s census total.

The population trend is the exception. It exists only where the ABS publishes a yearly series K-Stra loads, the council, and the app shows it for the councils inside the area.

An example

## What does the population of an area look like?

*[Image: K-Stra population results for a 10-minute drive from 300 Flinders Street, Townsville QLD: 41,910 residents, and the population of the City of Townsville from 2019 to 2025.]*

Townsville, QLD

41,910 residents within 10 minutesResidents, age and the council trend for 10 minutes by car from Flinders Street. ABS estimates at 30 June 2025; trend from 2019 to 2025.

Ten minutes by car from 300 Flinders Street, Townsville QLD reach 41,910 residents in 9,322 families. Their average age is 40.7, and 16.9% are aged 65 or over against 17.5% in Australia.

The City of Townsville grew from 193,687 residents in 2019 to 206,260 in 2025: 6.5% in 6 years, on average 1.08% a year. Children under 15 are 14.3% of the catchment, below the national 17.4%.

Population of the City of Townsville at 30 June of each year

30 June

Residents

2019

193,687

2020

194,679

2021

195,457

2022

197,694

2023

200,930

2024

203,972

2025

206,260

Source: K-Stra analysis of 1 November 2026; ABS Regional population and Regional population by age and sex, 30 June 2025.

Sources

## When are the population sources updated?

Population sources with the edition in K-Stra, publication date and next update

Source

Edition in K-Stra

Published

Next update of the source

[ABS Regional population (Estimated Resident Population)](https://www.abs.gov.au/statistics/people/population/regional-population/latest-release)

30 June 2025, by council

31 March 2026

25 March 2027 (30 June 2026)

[ABS Regional population by age and sex](https://www.abs.gov.au/statistics/people/population/regional-population-age-and-sex/latest-release)

30 June 2025

27 August 2026

31 August 2027

[ABS Census of Population and Housing 2021](https://www.abs.gov.au/media-centre/media-releases/2026-census-topics-and-data-release)

Census night, 10 August 2021

28 June 2022

June 2027, first results of the 2026 Census

The next council estimates, at 30 June 2026, are due on 25 March 2027, and the age and sex detail on 31 August 2027. The first results of the 2026 Census follow from June 2027; until then families, education and birthplace describe August 2021.

FAQ

## What else do people ask about population data?

### Why do age and families come from different years?

The ABS estimates population, sex and age every year, but families, education and birthplace are measured only by the census, every five years. K-Stra uses the most recent of each: 30 June 2025 for the first, August 2021 for the second, and every table says which.

### What is the old-age index?

The number of residents aged 65 and over for every 100 aged under 15. Above 100 there are more older residents than children. Around Flinders Street, Townsville, it is 118.

### Can I see the population trend of a postcode or a suburb?

Not year by year. The ABS publishes yearly estimates down to councils and SA2 areas, and K-Stra shows the series for councils. Postcodes and suburbs take the 2025 total of their addresses, with no earlier years.

### Does K-Stra count people who work or study in an area?

No. Every population figure counts residents, the people who usually live at an address. Workers, students, tourists and people passing through are not in any table.

Related pages

-   [Childcare and education](https://www.k-stra.com/industries/childcare-and-education/)
-   [All data in K-Stra](https://www.k-stra.com/product/data/)
-   [Work and income data](https://www.k-stra.com/product/data/work-and-income/)
-   [Housing and context data](https://www.k-stra.com/product/data/housing/)
-   [Demographic analysis](https://www.k-stra.com/solutions/demographic-analysis/)
-   [What is a catchment area?](https://www.k-stra.com/geomarketing/catchment-area/)
-   [Data updates log](https://www.k-stra.com/product/data/updates/)
-   [Fastest-growing councils](https://www.k-stra.com/insights/fastest-growing-councils-australia/)
-   [Youngest and oldest councils](https://www.k-stra.com/insights/youngest-and-oldest-councils/)
-   [Capital cities vs regional growth](https://www.k-stra.com/insights/capital-cities-vs-regional-growth/)

Try it

## Count who lives around an address.

Type an address, keep the drive-time bands and switch on Residents and Age.

[Open the app — free to explore](https://www.k-stra.com/a/?src=product-data-population)

Drawing the area is free
