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 Chatswood, accounting for 25.5% (6,527 people). This share was higher than Willoughby (C) (24.5%). Since 2016, the biggest change was in Parents and homebuilders (35 to 49), which increased by 866 people and 2.8 percentage points.
Section overview
Age structure - Service age groups
Chatswood - Total persons (Usual residence)
This table summarises service age groups for Chatswood in 2021 for persons, with comparison against Willoughby (C) and change since 2016.
Age structure - Service age groups snapshot
2021 distribution by category for Chatswood, with comparison markers for Willoughby (C).
Babies and pre-schoolers (0 to 4)
2021 count
1,280
% of total
5.0%
Change from 2016
-1.3pp
1,280
5.0%
-1.3pp
Primary schoolers (5 to 11)
2021 count
2,099
% of total
8.2%
Change from 2016
+0.6pp
2,099
8.2%
+0.6pp
Secondary schoolers (12 to 17)
2021 count
1,658
% of total
6.5%
Change from 2016
+1.2pp
1,658
6.5%
+1.2pp
Tertiary education and independence (18 to 24)
2021 count
2,051
% of total
8.0%
Change from 2016
-3.1pp
2,051
8.0%
-3.1pp
Young workforce (25 to 34)
2021 count
4,249
% of total
16.6%
Change from 2016
-3.4pp
4,249
16.6%
-3.4pp
Parents and homebuilders (35 to 49)
2021 count
6,527
% of total
25.5%
Change from 2016
+2.8pp
6,527
25.5%
+2.8pp
Older workers and pre-retirees (50 to 59)
2021 count
2,712
% of total
10.6%
Change from 2016
+0.5pp
2,712
10.6%
+0.5pp
Empty nesters and retirees (60 to 69)
2021 count
2,206
% of total
8.6%
Change from 2016
+0.3pp
2,206
8.6%
+0.3pp
Seniors (70 to 84)
2021 count
2,149
% of total
8.4%
Change from 2016
+1.8pp
2,149
8.4%
+1.8pp
Elderly aged (85 and over)
2021 count
625
% of total
2.4%
Change from 2016
+0.3pp
625
2.4%
+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)
-294
-1.3pp
Primary schoolers (5 to 11)
+216
+0.6pp
Secondary schoolers (12 to 17)
+332
+1.2pp
Tertiary education and independence (18 to 24)
-709
-3.1pp
Young workforce (25 to 34)
-724
-3.4pp
Parents and homebuilders (35 to 49)
+866
+2.8pp
Older workers and pre-retirees (50 to 59)
+197
+0.5pp
Empty nesters and retirees (60 to 69)
+141
+0.3pp
Seniors (70 to 84)
+503
+1.8pp
Elderly aged (85 and over)
+109
+0.3pp
Data table
Service age groups for Chatswood. 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) | 1,280 | 5.0% | 5.2% | 1,574 | 6.3% | 6.6% | -294 | -1.3pp |
| Primary schoolers (5 to 11) | 2,099 | 8.2% | 9.7% | 1,883 | 7.6% | 9.6% | +216 | +0.6pp |
| Secondary schoolers (12 to 17) | 1,658 | 6.5% | 7.6% | 1,326 | 5.3% | 6.4% | +332 | +1.2pp |
| Tertiary education and independence (18 to 24) | 2,051 | 8.0% | 7.2% | 2,760 | 11.1% | 8.1% | -709 | -3.1pp |
| Young workforce (25 to 34) | 4,249 | 16.6% | 12.4% | 4,973 | 20.0% | 15.2% | -724 | -3.4pp |
| Parents and homebuilders (35 to 49) | 6,527 | 25.5% | 24.5% | 5,661 | 22.7% | 23.9% | +866 | +2.8pp |
| Older workers and pre-retirees (50 to 59) | 2,712 | 10.6% | 12.4% | 2,515 | 10.1% | 11.7% | +197 | +0.5pp |
| Empty nesters and retirees (60 to 69) | 2,206 | 8.6% | 9.5% | 2,065 | 8.3% | 9.1% | +141 | +0.3pp |
| Seniors (70 to 84) | 2,149 | 8.4% | 8.9% | 1,646 | 6.6% | 7.0% | +503 | +1.8pp |
| Elderly aged (85 and over) | 625 | 2.4% | 2.6% | 516 | 2.1% | 2.3% | +109 | +0.3pp |
| Total | 25,553 | 100.0% | 100.0% | 24,913 | 100.0% | 100.0% | +640 | 0.0pp |