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, Young workforce (25 to 34) was the most common category among residents in Seaford Heights, accounting for 32.2% (347 people). This share was higher than Onkaparinga (C) (12.2%). Since 2016, the biggest change was in Young workforce (25 to 34), which increased by 327 people, while its share fell by 5.5 percentage points.
Section overview
Age structure - Service age groups
Seaford Heights - Total persons (Usual residence)
This table summarises service age groups for Seaford Heights in 2021 for persons, with comparison against Onkaparinga (C) and change since 2016.
Age structure - Service age groups snapshot
2021 distribution by category for Seaford Heights, with comparison markers for Onkaparinga (C).
Babies and pre-schoolers (0 to 4)
2021 count
113
% of total
10.5%
Change from 2016
+10.5pp
113
10.5%
+10.5pp
Primary schoolers (5 to 11)
2021 count
113
% of total
10.5%
Change from 2016
+10.5pp
113
10.5%
+10.5pp
Secondary schoolers (12 to 17)
2021 count
56
% of total
5.2%
Change from 2016
-0.5pp
56
5.2%
-0.5pp
Tertiary education and independence (18 to 24)
2021 count
102
% of total
9.5%
Change from 2016
-1.8pp
102
9.5%
-1.8pp
Young workforce (25 to 34)
2021 count
347
% of total
32.2%
Change from 2016
-5.5pp
347
32.2%
-5.5pp
Parents and homebuilders (35 to 49)
2021 count
200
% of total
18.5%
Change from 2016
+12.8pp
200
18.5%
+12.8pp
Older workers and pre-retirees (50 to 59)
2021 count
87
% of total
8.1%
Change from 2016
-5.1pp
87
8.1%
-5.1pp
Empty nesters and retirees (60 to 69)
2021 count
47
% of total
4.4%
Change from 2016
-1.3pp
47
4.4%
-1.3pp
Seniors (70 to 84)
2021 count
17
% of total
1.6%
Change from 2016
+1.6pp
17
1.6%
+1.6pp
Elderly aged (85 and over)
2021 count
5
% of total
0.5%
Change from 2016
+0.5pp
5
0.5%
+0.5pp
Chart view
Age structure - Service age groups change
Absolute change in category counts between 2016 and 2021.
Babies and pre-schoolers (0 to 4)
+113
+10.5pp
Primary schoolers (5 to 11)
+113
+10.5pp
Secondary schoolers (12 to 17)
+53
-0.5pp
Tertiary education and independence (18 to 24)
+96
-1.8pp
Young workforce (25 to 34)
+327
-5.5pp
Parents and homebuilders (35 to 49)
+197
+12.8pp
Older workers and pre-retirees (50 to 59)
+80
-5.1pp
Empty nesters and retirees (60 to 69)
+44
-1.3pp
Seniors (70 to 84)
+17
+1.6pp
Elderly aged (85 and over)
+5
+0.5pp
Data table
Service age groups for Seaford Heights. Age structure - Service age groups. 2021 and 2016 counts, percentages, and change compared with Onkaparinga (C).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Onkaparinga (C)% | Count | % | Onkaparinga (C)% | Count | pp | |
| Babies and pre-schoolers (0 to 4) | 113 | 10.5% | 5.4% | 0 | 0.0% | 6.2% | +113 | +10.5pp |
| Primary schoolers (5 to 11) | 113 | 10.5% | 8.6% | 0 | 0.0% | 8.9% | +113 | +10.5pp |
| Secondary schoolers (12 to 17) | 56 | 5.2% | 7.3% | 3 | 5.7% | 7.5% | +53 | -0.5pp |
| Tertiary education and independence (18 to 24) | 102 | 9.5% | 7.9% | 6 | 11.3% | 8.4% | +96 | -1.8pp |
| Young workforce (25 to 34) | 347 | 32.2% | 12.2% | 20 | 37.7% | 12.4% | +327 | -5.5pp |
| Parents and homebuilders (35 to 49) | 200 | 18.5% | 19.2% | 3 | 5.7% | 19.7% | +197 | +12.8pp |
| Older workers and pre-retirees (50 to 59) | 87 | 8.1% | 13.1% | 7 | 13.2% | 13.3% | +80 | -5.1pp |
| Empty nesters and retirees (60 to 69) | 47 | 4.4% | 12.3% | 3 | 5.7% | 12.4% | +44 | -1.3pp |
| Seniors (70 to 84) | 17 | 1.6% | 11.8% | 0 | 0.0% | 9.1% | +17 | +1.6pp |
| Elderly aged (85 and over) | 5 | 0.5% | 2.2% | 0 | 0.0% | 2.1% | +5 | +0.5pp |
| Total | 1,079 | 100.0% | 100.0% | 53 | 100.0% | 100.0% | +1,026 | 0.0pp |