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-high income quartile held the largest share among residents aged 15 and over in Casey (C), accounting for 29.4%.

Section overview

Individual income quartiles

Casey (C) - Persons aged 15+ (Usual residence)

This table summarises individual income quartiles for Casey (C) in 2021 for persons, with comparison against Greater Melbourne and change since 2016.

Individual income quartiles snapshot

2021 distribution by category for Casey (C), with comparison markers for Greater Melbourne.

Casey (C)
Greater Melbourne

Lowest group

2021 count

72,841

% of total

27.5%

Change from 2016

+0.2pp

Medium lowest

2021 count

62,405

% of total

23.5%

Change from 2016

+0.6pp

Medium highest

2021 count

77,900

% of total

29.4%

Change from 2016

+0.5pp

Highest group

2021 count

52,115

% of total

19.6%

Change from 2016

-1.3pp

Data table

Individual income quartiles for Casey (C). Individual income quartiles. 2021 and 2016 counts, percentages, and change compared with Greater Melbourne.

Individual income quartiles for Casey (C). Individual income quartiles. 2021 and 2016 counts, percentages, and change compared with Greater Melbourne.
Individual income quartiles for Casey (C). Individual income quartiles. 2021 and 2016 counts, percentages, and change compared with Greater Melbourne.
Category20212016Change
Count%Greater Melbourne%Count%Greater Melbourne%Countpp
Lowest group72,84127.5%25.2%58,59827.3%25.7%+14,243+0.2pp
Medium lowest62,40523.5%23.2%48,98022.9%22.8%+13,425+0.6pp
Medium highest77,90029.4%24.8%62,02028.9%24.6%+15,880+0.5pp
Highest group52,11519.6%26.8%44,68120.9%26.8%+7,434-1.3pp
Total persons aged 15+265,261100.0%100.0%214,279100.0%100.0%+50,9820.0pp