Population
Service age groups
About this topic
Service age groups divide the population into broad life-stage bands such as children, young adults, working-age adults, and older people. The groupings are designed to reflect typical demand for age-based services and facilities rather than exact five-year cohorts.
This view is useful for planning childcare, schools, recreation, aged services, and other community infrastructure. It works best alongside five year age groups, household type, and dwelling data, which add more detail about who is living in an area and how needs may change over time.
Interpretation notes
- This is a derived grouping rather than a direct Census question, so the age bands are planning-oriented summaries built from standard age data.
- Percentages relate to the total population; use five year age groups when exact cohort detail matters.
Related topics
Key insight
In 2021, Empty nesters and retirees (60 to 69) was the most common category among residents in Irwin (S), accounting for 18.9% (697 people). This share was higher than Regional WA (12.4%). Since 2016, the biggest change was in Seniors (70 to 84), which increased by 167 people and 4.1 percentage points.
Section overview
Age structure - Service age groups
Irwin (S) - Total persons (Usual residence)
This table summarises service age groups for Irwin (S) in 2021 for persons, with comparison against Regional WA and change since 2016.
Age structure - Service age groups snapshot
2021 distribution by category for Irwin (S), with comparison markers for Regional WA.
Babies and pre-schoolers (0 to 4)
2021 count
139
% of total
3.8%
Change from 2016
-0.9pp
139
3.8%
-0.9pp
Primary schoolers (5 to 11)
2021 count
260
% of total
7.1%
Change from 2016
-1.9pp
260
7.1%
-1.9pp
Secondary schoolers (12 to 17)
2021 count
270
% of total
7.3%
Change from 2016
-0.1pp
270
7.3%
-0.1pp
Tertiary education and independence (18 to 24)
2021 count
186
% of total
5.1%
Change from 2016
+0.7pp
186
5.1%
+0.7pp
Young workforce (25 to 34)
2021 count
218
% of total
5.9%
Change from 2016
-1.7pp
218
5.9%
-1.7pp
Parents and homebuilders (35 to 49)
2021 count
588
% of total
16.0%
Change from 2016
-0.6pp
588
16.0%
-0.6pp
Older workers and pre-retirees (50 to 59)
2021 count
558
% of total
15.2%
Change from 2016
+0.2pp
558
15.2%
+0.2pp
Empty nesters and retirees (60 to 69)
2021 count
697
% of total
18.9%
Change from 2016
+0.9pp
697
18.9%
+0.9pp
Seniors (70 to 84)
2021 count
678
% of total
18.4%
Change from 2016
+4.1pp
678
18.4%
+4.1pp
Elderly aged (85 and over)
2021 count
78
% of total
2.1%
Change from 2016
-0.3pp
78
2.1%
-0.3pp
Chart view
Age structure - Service age groups change
Absolute change in category counts between 2016 and 2021.
Babies and pre-schoolers (0 to 4)
-28
-0.9pp
Primary schoolers (5 to 11)
-60
-1.9pp
Secondary schoolers (12 to 17)
+6
-0.1pp
Tertiary education and independence (18 to 24)
+30
+0.7pp
Young workforce (25 to 34)
-53
-1.7pp
Parents and homebuilders (35 to 49)
-5
-0.6pp
Older workers and pre-retirees (50 to 59)
+23
+0.2pp
Empty nesters and retirees (60 to 69)
+53
+0.9pp
Seniors (70 to 84)
+167
+4.1pp
Elderly aged (85 and over)
-9
-0.3pp
Data table
Service age groups for Irwin (S). Age structure - Service age groups. 2021 and 2016 counts, percentages, and change compared with Regional WA.
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Regional WA% | Count | % | Regional WA% | Count | pp | |
| Babies and pre-schoolers (0 to 4) | 139 | 3.8% | 6.0% | 167 | 4.7% | 6.6% | -28 | -0.9pp |
| Primary schoolers (5 to 11) | 260 | 7.1% | 9.5% | 320 | 9.0% | 9.8% | -60 | -1.9pp |
| Secondary schoolers (12 to 17) | 270 | 7.3% | 7.6% | 264 | 7.4% | 7.4% | +6 | -0.1pp |
| Tertiary education and independence (18 to 24) | 186 | 5.1% | 6.7% | 156 | 4.4% | 7.0% | +30 | +0.7pp |
| Young workforce (25 to 34) | 218 | 5.9% | 12.5% | 271 | 7.6% | 13.6% | -53 | -1.7pp |
| Parents and homebuilders (35 to 49) | 588 | 16.0% | 19.9% | 593 | 16.6% | 20.8% | -5 | -0.6pp |
| Older workers and pre-retirees (50 to 59) | 558 | 15.2% | 13.7% | 535 | 15.0% | 14.1% | +23 | +0.2pp |
| Empty nesters and retirees (60 to 69) | 697 | 18.9% | 12.4% | 644 | 18.0% | 11.3% | +53 | +0.9pp |
| Seniors (70 to 84) | 678 | 18.4% | 10.1% | 511 | 14.3% | 7.8% | +167 | +4.1pp |
| Elderly aged (85 and over) | 78 | 2.1% | 1.7% | 87 | 2.4% | 1.5% | -9 | -0.3pp |
| Total | 3,680 | 100.0% | 100.0% | 3,569 | 100.0% | 100.0% | +111 | 0.0pp |