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, Parents and homebuilders (35 to 49) was the most common category among residents in Castlereagh, accounting for 18.9% (236 people). This share was lower than Penrith (C) (21%). Since 2016, the biggest change was in Older workers and pre-retirees (50 to 59), which decreased by 48 people and 4.8 percentage points.
Section overview
Age structure - Service age groups
Castlereagh - Total persons (Usual residence)
This table summarises service age groups for Castlereagh in 2021 for persons, with comparison against Penrith (C) and change since 2016.
Age structure - Service age groups snapshot
2021 distribution by category for Castlereagh, with comparison markers for Penrith (C).
Babies and pre-schoolers (0 to 4)
2021 count
82
% of total
6.6%
Change from 2016
+1.0pp
82
6.6%
+1.0pp
Primary schoolers (5 to 11)
2021 count
133
% of total
10.7%
Change from 2016
+2.1pp
133
10.7%
+2.1pp
Secondary schoolers (12 to 17)
2021 count
99
% of total
7.9%
Change from 2016
+0.3pp
99
7.9%
+0.3pp
Tertiary education and independence (18 to 24)
2021 count
91
% of total
7.3%
Change from 2016
-2.4pp
91
7.3%
-2.4pp
Young workforce (25 to 34)
2021 count
145
% of total
11.6%
Change from 2016
+1.1pp
145
11.6%
+1.1pp
Parents and homebuilders (35 to 49)
2021 count
236
% of total
18.9%
Change from 2016
+1.8pp
236
18.9%
+1.8pp
Older workers and pre-retirees (50 to 59)
2021 count
133
% of total
10.7%
Change from 2016
-4.8pp
133
10.7%
-4.8pp
Empty nesters and retirees (60 to 69)
2021 count
171
% of total
13.7%
Change from 2016
-0.1pp
171
13.7%
-0.1pp
Seniors (70 to 84)
2021 count
115
% of total
9.2%
Change from 2016
+1.1pp
115
9.2%
+1.1pp
Elderly aged (85 and over)
2021 count
17
% of total
1.4%
Change from 2016
+0.6pp
17
1.4%
+0.6pp
Chart view
Age structure - Service age groups change
Absolute change in category counts between 2016 and 2021.
Babies and pre-schoolers (0 to 4)
+17
+1.0pp
Primary schoolers (5 to 11)
+32
+2.1pp
Secondary schoolers (12 to 17)
+10
+0.3pp
Tertiary education and independence (18 to 24)
-23
-2.4pp
Young workforce (25 to 34)
+22
+1.1pp
Parents and homebuilders (35 to 49)
+36
+1.8pp
Older workers and pre-retirees (50 to 59)
-48
-4.8pp
Empty nesters and retirees (60 to 69)
+9
-0.1pp
Seniors (70 to 84)
+20
+1.1pp
Elderly aged (85 and over)
+8
+0.6pp
Data table
Service age groups for Castlereagh. Age structure - Service age groups. 2021 and 2016 counts, percentages, and change compared with Penrith (C).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Penrith (C)% | Count | % | Penrith (C)% | Count | pp | |
| Babies and pre-schoolers (0 to 4) | 82 | 6.6% | 7.2% | 65 | 5.6% | 7.4% | +17 | +1.0pp |
| Primary schoolers (5 to 11) | 133 | 10.7% | 9.9% | 101 | 8.6% | 9.8% | +32 | +2.1pp |
| Secondary schoolers (12 to 17) | 99 | 7.9% | 7.8% | 89 | 7.6% | 7.8% | +10 | +0.3pp |
| Tertiary education and independence (18 to 24) | 91 | 7.3% | 9.3% | 114 | 9.7% | 9.9% | -23 | -2.4pp |
| Young workforce (25 to 34) | 145 | 11.6% | 15.2% | 123 | 10.5% | 15.4% | +22 | +1.1pp |
| Parents and homebuilders (35 to 49) | 236 | 18.9% | 21.0% | 200 | 17.1% | 20.5% | +36 | +1.8pp |
| Older workers and pre-retirees (50 to 59) | 133 | 10.7% | 11.4% | 181 | 15.5% | 12.3% | -48 | -4.8pp |
| Empty nesters and retirees (60 to 69) | 171 | 13.7% | 9.5% | 162 | 13.8% | 9.7% | +9 | -0.1pp |
| Seniors (70 to 84) | 115 | 9.2% | 7.5% | 95 | 8.1% | 6.0% | +20 | +1.1pp |
| Elderly aged (85 and over) | 17 | 1.4% | 1.2% | 9 | 0.8% | 1.2% | +8 | +0.6pp |
| Total | 1,248 | 100.0% | 100.0% | 1,171 | 100.0% | 100.0% | +77 | 0.0pp |