Income

Individual income quartiles

About this topic

Individual income quartiles group people aged 15 years and over into four evenly sized income ranges so the distribution of personal income can be compared objectively across areas and over time. The quartile method focuses on relative position in the income distribution rather than raw dollar brackets.

This topic is useful because direct income amounts are affected by inflation and wider economic change. Quartiles provide a clearer way to compare whether an area is becoming relatively lower, middle, or higher income over time.

Interpretation notes

  • This is a derived distribution of personal income for people aged 15 years and over, with each quartile representing a quarter of the income distribution.
  • Quartiles show relative position rather than fixed dollar brackets, which makes them more robust for comparisons over time.

Key insight

In 2021, the medium-low income quartile held the largest share among residents aged 15 and over in Ashby (WA), accounting for 30.2%.

Section overview

Individual income quartiles

Ashby (WA) - Persons aged 15+ (Usual residence)

This table summarises individual income quartiles for Ashby (WA) in 2021 for persons, with comparison against Wanneroo (C) and change since 2016.

Individual income quartiles snapshot

2021 distribution by category for Ashby (WA), with comparison markers for Wanneroo (C).

Ashby (WA)
Wanneroo (C)

Lowest group

2021 count

482

% of total

22.3%

Change from 2016

+1.3pp

Medium lowest

2021 count

653

% of total

30.2%

Change from 2016

+3.7pp

Medium highest

2021 count

539

% of total

24.9%

Change from 2016

+1.5pp

Highest group

2021 count

491

% of total

22.7%

Change from 2016

-6.4pp

Data table

Individual income quartiles for Ashby (WA). Individual income quartiles. 2021 and 2016 counts, percentages, and change compared with Wanneroo (C).

Individual income quartiles for Ashby (WA). Individual income quartiles. 2021 and 2016 counts, percentages, and change compared with Wanneroo (C).
Individual income quartiles for Ashby (WA). Individual income quartiles. 2021 and 2016 counts, percentages, and change compared with Wanneroo (C).
Category20212016Change
Count%Wanneroo (C)%Count%Wanneroo (C)%Countpp
Lowest group48222.3%25.7%41121.0%25.5%+71+1.3pp
Medium lowest65330.2%23.7%51926.5%21.3%+134+3.7pp
Medium highest53924.9%25.6%45823.4%24.7%+81+1.5pp
Highest group49122.7%25.0%56929.1%28.5%-78-6.4pp
Total persons aged 15+2,165100.0%100.0%1,957100.0%100.0%+2080.0pp