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 Castle Cove, accounting for 18.8% (496 people). This share was lower than Willoughby (C) (24.5%). Since 2016, the biggest change was in Secondary schoolers (12 to 17), which increased by 55 people and 1.8 percentage points.
Section overview
Age structure - Service age groups
Castle Cove - Total persons (Usual residence)
This table summarises service age groups for Castle Cove in 2021 for persons, with comparison against Willoughby (C) and change since 2016.
Age structure - Service age groups snapshot
2021 distribution by category for Castle Cove, with comparison markers for Willoughby (C).
Babies and pre-schoolers (0 to 4)
2021 count
96
% of total
3.6%
Change from 2016
-2.0pp
96
3.6%
-2.0pp
Primary schoolers (5 to 11)
2021 count
284
% of total
10.7%
Change from 2016
+0.2pp
284
10.7%
+0.2pp
Secondary schoolers (12 to 17)
2021 count
274
% of total
10.4%
Change from 2016
+1.8pp
274
10.4%
+1.8pp
Tertiary education and independence (18 to 24)
2021 count
208
% of total
7.9%
Change from 2016
+0.5pp
208
7.9%
+0.5pp
Young workforce (25 to 34)
2021 count
128
% of total
4.8%
Change from 2016
-1.6pp
128
4.8%
-1.6pp
Parents and homebuilders (35 to 49)
2021 count
496
% of total
18.8%
Change from 2016
-0.5pp
496
18.8%
-0.5pp
Older workers and pre-retirees (50 to 59)
2021 count
401
% of total
15.2%
Change from 2016
+0.2pp
401
15.2%
+0.2pp
Empty nesters and retirees (60 to 69)
2021 count
315
% of total
11.9%
Change from 2016
+0.1pp
315
11.9%
+0.1pp
Seniors (70 to 84)
2021 count
345
% of total
13.1%
Change from 2016
+1.7pp
345
13.1%
+1.7pp
Elderly aged (85 and over)
2021 count
99
% of total
3.7%
Change from 2016
0.0pp
99
3.7%
0.0pp
Chart view
Age structure - Service age groups change
Absolute change in category counts between 2016 and 2021.
Babies and pre-schoolers (0 to 4)
-47
-2.0pp
Primary schoolers (5 to 11)
+17
+0.2pp
Secondary schoolers (12 to 17)
+55
+1.8pp
Tertiary education and independence (18 to 24)
+19
+0.5pp
Young workforce (25 to 34)
-36
-1.6pp
Parents and homebuilders (35 to 49)
+2
-0.5pp
Older workers and pre-retirees (50 to 59)
+17
+0.2pp
Empty nesters and retirees (60 to 69)
+14
+0.1pp
Seniors (70 to 84)
+54
+1.7pp
Elderly aged (85 and over)
+5
0.0pp
Data table
Service age groups for Castle Cove. Age structure - Service age groups. 2021 and 2016 counts, percentages, and change compared with Willoughby (C).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Willoughby (C)% | Count | % | Willoughby (C)% | Count | pp | |
| Babies and pre-schoolers (0 to 4) | 96 | 3.6% | 5.2% | 143 | 5.6% | 6.6% | -47 | -2.0pp |
| Primary schoolers (5 to 11) | 284 | 10.7% | 9.7% | 267 | 10.5% | 9.6% | +17 | +0.2pp |
| Secondary schoolers (12 to 17) | 274 | 10.4% | 7.6% | 219 | 8.6% | 6.4% | +55 | +1.8pp |
| Tertiary education and independence (18 to 24) | 208 | 7.9% | 7.2% | 189 | 7.4% | 8.1% | +19 | +0.5pp |
| Young workforce (25 to 34) | 128 | 4.8% | 12.4% | 164 | 6.4% | 15.2% | -36 | -1.6pp |
| Parents and homebuilders (35 to 49) | 496 | 18.8% | 24.5% | 494 | 19.3% | 23.9% | +2 | -0.5pp |
| Older workers and pre-retirees (50 to 59) | 401 | 15.2% | 12.4% | 384 | 15.0% | 11.7% | +17 | +0.2pp |
| Empty nesters and retirees (60 to 69) | 315 | 11.9% | 9.5% | 301 | 11.8% | 9.1% | +14 | +0.1pp |
| Seniors (70 to 84) | 345 | 13.1% | 8.9% | 291 | 11.4% | 7.0% | +54 | +1.7pp |
| Elderly aged (85 and over) | 99 | 3.7% | 2.6% | 94 | 3.7% | 2.3% | +5 | 0.0pp |
| Total | 2,643 | 100.0% | 100.0% | 2,554 | 100.0% | 100.0% | +89 | 0.0pp |