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, Older workers and pre-retirees (50 to 59) was the most common category among residents in One Tree Hill, accounting for 21.2% (221 people). This share was higher than Playford (C) (11.6%). Since 2016, the biggest change was in Parents and homebuilders (35 to 49), which decreased by 40 people and 2.9 percentage points.
Section overview
Age structure - Service age groups
One Tree Hill - Total persons (Usual residence)
This table summarises service age groups for One Tree Hill in 2021 for persons, with comparison against Playford (C) and change since 2016.
Age structure - Service age groups snapshot
2021 distribution by category for One Tree Hill, with comparison markers for Playford (C).
Babies and pre-schoolers (0 to 4)
2021 count
46
% of total
4.4%
Change from 2016
-0.2pp
46
4.4%
-0.2pp
Primary schoolers (5 to 11)
2021 count
99
% of total
9.5%
Change from 2016
+0.9pp
99
9.5%
+0.9pp
Secondary schoolers (12 to 17)
2021 count
88
% of total
8.4%
Change from 2016
-1.0pp
88
8.4%
-1.0pp
Tertiary education and independence (18 to 24)
2021 count
109
% of total
10.5%
Change from 2016
+0.6pp
109
10.5%
+0.6pp
Young workforce (25 to 34)
2021 count
66
% of total
6.3%
Change from 2016
-2.2pp
66
6.3%
-2.2pp
Parents and homebuilders (35 to 49)
2021 count
173
% of total
16.6%
Change from 2016
-2.9pp
173
16.6%
-2.9pp
Older workers and pre-retirees (50 to 59)
2021 count
221
% of total
21.2%
Change from 2016
-0.2pp
221
21.2%
-0.2pp
Empty nesters and retirees (60 to 69)
2021 count
150
% of total
14.4%
Change from 2016
+0.5pp
150
14.4%
+0.5pp
Seniors (70 to 84)
2021 count
104
% of total
10.0%
Change from 2016
+2.4pp
104
10.0%
+2.4pp
Elderly aged (85 and over)
2021 count
12
% of total
1.2%
Change from 2016
-0.5pp
12
1.2%
-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)
-4
-0.2pp
Primary schoolers (5 to 11)
+5
+0.9pp
Secondary schoolers (12 to 17)
-15
-1.0pp
Tertiary education and independence (18 to 24)
+1
+0.6pp
Young workforce (25 to 34)
-27
-2.2pp
Parents and homebuilders (35 to 49)
-40
-2.9pp
Older workers and pre-retirees (50 to 59)
-13
-0.2pp
Empty nesters and retirees (60 to 69)
-2
+0.5pp
Seniors (70 to 84)
+21
+2.4pp
Elderly aged (85 and over)
-7
-0.5pp
Data table
Service age groups for One Tree Hill. Age structure - Service age groups. 2021 and 2016 counts, percentages, and change compared with Playford (C).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Playford (C)% | Count | % | Playford (C)% | Count | pp | |
| Babies and pre-schoolers (0 to 4) | 46 | 4.4% | 7.5% | 50 | 4.6% | 8.6% | -4 | -0.2pp |
| Primary schoolers (5 to 11) | 99 | 9.5% | 11.0% | 94 | 8.6% | 10.6% | +5 | +0.9pp |
| Secondary schoolers (12 to 17) | 88 | 8.4% | 8.1% | 103 | 9.4% | 7.8% | -15 | -1.0pp |
| Tertiary education and independence (18 to 24) | 109 | 10.5% | 9.5% | 108 | 9.9% | 10.5% | +1 | +0.6pp |
| Young workforce (25 to 34) | 66 | 6.3% | 15.9% | 93 | 8.5% | 15.3% | -27 | -2.2pp |
| Parents and homebuilders (35 to 49) | 173 | 16.6% | 18.5% | 213 | 19.5% | 18.2% | -40 | -2.9pp |
| Older workers and pre-retirees (50 to 59) | 221 | 21.2% | 11.6% | 234 | 21.4% | 12.3% | -13 | -0.2pp |
| Empty nesters and retirees (60 to 69) | 150 | 14.4% | 9.1% | 152 | 13.9% | 8.4% | -2 | +0.5pp |
| Seniors (70 to 84) | 104 | 10.0% | 7.2% | 83 | 7.6% | 6.9% | +21 | +2.4pp |
| Elderly aged (85 and over) | 12 | 1.2% | 1.6% | 19 | 1.7% | 1.5% | -7 | -0.5pp |
| Total | 1,043 | 100.0% | 100.0% | 1,095 | 100.0% | 100.0% | -52 | 0.0pp |