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 Silver Sands, accounting for 29.5%.
Section overview
Individual income quartiles
Silver Sands - Persons aged 15+ (Usual residence)
This table summarises individual income quartiles for Silver Sands in 2021 for persons, with comparison against Mandurah (C) and change since 2016.
Individual income quartiles snapshot
2021 distribution by category for Silver Sands, with comparison markers for Mandurah (C).
Lowest group
2021 count
296
% of total
26.2%
Change from 2016
+2.5pp
296
26.2%
+2.5pp
Medium lowest
2021 count
334
% of total
29.5%
Change from 2016
+2.3pp
334
29.5%
+2.3pp
Medium highest
2021 count
242
% of total
21.4%
Change from 2016
-1.2pp
242
21.4%
-1.2pp
Highest group
2021 count
259
% of total
22.9%
Change from 2016
-3.6pp
259
22.9%
-3.6pp
Chart view
Individual income quartiles change
Absolute change in category counts between 2016 and 2021.
Lowest group
+61
+2.5pp
Medium lowest
+64
+2.3pp
Medium highest
+18
-1.2pp
Highest group
-4
-3.6pp
Data table
Individual income quartiles for Silver Sands. Individual income quartiles. 2021 and 2016 counts, percentages, and change compared with Mandurah (C).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Mandurah (C)% | Count | % | Mandurah (C)% | Count | pp | |
| Lowest group | 296 | 26.2% | 28.4% | 235 | 23.7% | 25.5% | +61 | +2.5pp |
| Medium lowest | 334 | 29.5% | 30.4% | 270 | 27.2% | 29.9% | +64 | +2.3pp |
| Medium highest | 242 | 21.4% | 19.3% | 224 | 22.6% | 20.6% | +18 | -1.2pp |
| Highest group | 259 | 22.9% | 21.8% | 263 | 26.5% | 24.0% | -4 | -3.6pp |
| Total persons aged 15+ | 1,131 | 100.0% | 100.0% | 992 | 100.0% | 100.0% | +139 | 0.0pp |