Understanding who lives in your catchment in Placemaker

Census data in Placemaker shows who lives in your catchment – their background, education, work, income, housing and households. Forecasts tell you how many people will live there and when. Read the two together to plan a service that fits the community, not only its size.

Key concepts

Count and share

A count tells you how many people or households a service could reach. A share tells you how much of the area they make up. Use the count to size a service and the share to see what makes an area different. A large catchment can hold hundreds of people from a group that is only a small share of its population.

Change over time

Most datasets cover the 2011, 2016 and 2021 Censuses. Choose a year range to see how an area has changed. Change (number) shows how many more or fewer people there are. Change (percentage points) shows how their share has moved – a share that goes from 10% to 12% has risen 2 percentage points. A count can rise while its share falls, when the rest of the population grows faster.

Every Census year for these datasets is shown on 2021 boundaries, so you're comparing the same area each time. Household income, median household income, median rent and median mortgage repayment are shown for each Census on that year's own boundaries, so they have no change measure.

Benchmark

A figure means more beside a comparison. In Insights, each chart shows your catchment beside a benchmark area. Look for where your catchment is well above or below it – that is what sets your community apart.

Small numbers

The ABS makes small random adjustments to Census counts to protect privacy. The effect is largest for small groups in small areas. Areas with very low counts are marked 'Suppressed (low counts)' and shaded grey. For a small group, read the figure for your whole catchment or at SA2 rather than for a single SA1.

How this applies in Placemaker

Shade the map by one measure to see where a group lives across a region. Then open Insights for a catchment to read every theme beside a benchmark. Each theme below sets out the question it helps answer, what to look for and what to watch out for.

Cultural diversity

Question it answers: who lives in your catchment, where they were born and what languages they speak at home.

Look for:

• Areas where a country of birth or language is well above the benchmark. These show where services in a language, or culturally specific programs, will reach the most people.
• A group whose share has risen between Census years. It can point to an emerging community, often ahead of the services it needs.
• The First Nations count as well as the share. A small share can still mean hundreds of people in a large catchment.

Watch out for:

• Small groups in a single SA1. Read them for your whole catchment or at SA2.
• Broad groups such as 'Christian total' or 'Total overseas born'. Open the detailed categories to see the communities inside them.
• First Nations change at SA1. The 2016 Census gives a count but no share at SA1, so compare shares at SA2 or above.

Education

Question it answers: who is studying in your catchment, at what level and in which school sector – and what qualifications adults hold.

Look for:

• Market share by school type. It shows the share of school-aged children attending government, Catholic and independent schools, and how that has moved between Censuses.
• Type of educational institution, to see how many people attend pre-school, primary, secondary, TAFE or university.
• Non-school qualification level, to see the skills of adults aged 15 and over – a signal for workforce and adult learning services.

Watch out for:

• Market share is calculated by Informed Decisions from Census answers, not published by the ABS. Shares across school types don't add up to 100%.
• Census night captures where students live, not where they go to school. Pair it with school enrolment data to see where they travel.

Work and income

Question it answers: how people in your catchment earn a living and how much economic advantage or disadvantage they have.

Look for:

• Median household income and income bands against the benchmark. They show capacity to pay for a service.
• Unemployment and participation rates, and how they have moved.
• SEIFA scores, to find areas of relative disadvantage where a service may be most needed.
• Households with no motor vehicle. They rely on public transport or walking, so travel distance matters more to them.

Watch out for:

• Income bands change each Census, so compare income within one Census year, not across years.
• A SEIFA score describes an area as a whole, not every household in it. SEIFA covers 2021 only.

Health and care

Question it answers: how many people need help with everyday activities because of disability, a long-term health condition or old age.

Look for:

• Areas where the share needing assistance is above the benchmark. They point to demand for aged care, disability and home support services.
• Growth in the count between Census years, alongside the forecast growth in older age groups.

Watch out for:

• Need for assistance counts people who need help with self-care, mobility or communication. It does not measure every person with a disability or health condition.

Housing tenure and costs

Question it answers: whether people own, are buying or rent their home, and what they pay.

Look for:

• A high share of renting households. Renters tend to move more often, which can change who a service reaches from year to year.
• Social housing, which can point to households with greater need.
• Median rent and mortgage repayments against the benchmark, as a sign of housing stress and spare household income.

Watch out for:

• Rent is weekly and mortgage repayments are monthly, so don't compare the two figures directly.
• Median rent and mortgage repayments have no change measure. Compare each Census year on its own.

Households

Question it answers: who people live with and what stage of life their household is in.

Look for:

• Household life stage, such as couples with young children or older couples without children. It shows the mix of families an early learning, school or aged care service will draw from.
• Lone person households, especially older people living alone.
• Change between Census years, to see whether an area is getting younger or older as households move through life stages.

Watch out for:

• Household data counts households, not people. A catchment with fewer, larger households can hold as many people as one with many lone person households.

Frequently asked questions

Q: My catchment's count went up but its share went down. Which one matters?

A: Both. The count tells you more people from that group live there, so demand may have grown. The share tells you the rest of the population grew faster. Use the count to size a service and the share to see how the community is changing.

Q: Can I compare 2011 and 2021 for an SA1?

A: Yes, for datasets with a change measure. Every Census year is shown on 2021 boundaries, so you're comparing the same area. For small groups, read change for your whole catchment or at SA2, because small counts move more from privacy adjustments.

Q: Why can't I see change over time for income or rent?

A: Income bands change each Census, and these figures are shown on each year's own boundaries. Compare them within one Census year.

Q: Does the Census tell me how many people will live in my catchment in future?

A: No. The Census describes who lived there on Census night. Informed Decisions population and dwelling forecasts show how many people and dwellings there will be in future years. Use the Census for who and the forecasts for how many and when.

Q: What should I look at first?

A: Start with the theme closest to the service you plan. Compare your catchment with the benchmark, then look at how it has changed since 2011.

Related articles

• What demographic data is available in Placemaker?
• How to shade the map by demographic data in Placemaker
• How to read demographic charts for a catchment in Placemaker