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 Mount Martin, accounting for 27.2%.
Section overview
Individual income quartiles
Mount Martin - Persons aged 15+ (Usual residence)
This table summarises individual income quartiles for Mount Martin in 2021 for persons, with comparison against Mackay (R) and change since 2016.
Individual income quartiles snapshot
2021 distribution by category for Mount Martin, with comparison markers for Mackay (R).
Lowest group
2021 count
35
% of total
23.8%
Change from 2016
-1.9pp
35
23.8%
-1.9pp
Medium lowest
2021 count
40
% of total
27.2%
Change from 2016
+3.7pp
40
27.2%
+3.7pp
Medium highest
2021 count
34
% of total
23.1%
Change from 2016
+0.3pp
34
23.1%
+0.3pp
Highest group
2021 count
38
% of total
25.9%
Change from 2016
-2.0pp
38
25.9%
-2.0pp
Chart view
Individual income quartiles change
Absolute change in category counts between 2016 and 2021.
Lowest group
0
-1.9pp
Medium lowest
+8
+3.7pp
Medium highest
+3
+0.3pp
Highest group
0
-2.0pp
Data table
Individual income quartiles for Mount Martin. Individual income quartiles. 2021 and 2016 counts, percentages, and change compared with Mackay (R).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Mackay (R)% | Count | % | Mackay (R)% | Count | pp | |
| Lowest group | 35 | 23.8% | 22.6% | 35 | 25.7% | 23.1% | 0 | -1.9pp |
| Medium lowest | 40 | 27.2% | 24.6% | 32 | 23.5% | 24.0% | +8 | +3.7pp |
| Medium highest | 34 | 23.1% | 24.6% | 31 | 22.8% | 24.2% | +3 | +0.3pp |
| Highest group | 38 | 25.9% | 28.2% | 38 | 27.9% | 28.7% | 0 | -2.0pp |
| Total persons aged 15+ | 147 | 100.0% | 100.0% | 136 | 100.0% | 100.0% | +11 | 0.0pp |