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 North Rocks (part), accounting for 22.6% (2,066 people). This share was lower than Parramatta (C) (23.8%). Since 2016, the biggest change was in Parents and homebuilders (35 to 49), which increased by 399 people and 1.7 percentage points.
Section overview
Age structure - Service age groups
North Rocks (part) - Total persons (Usual residence)
This table summarises service age groups for North Rocks (part) in 2021 for persons, with comparison against Parramatta (C) and change since 2016.
Age structure - Service age groups snapshot
2021 distribution by category for North Rocks (part), with comparison markers for Parramatta (C).
Babies and pre-schoolers (0 to 4)
2021 count
486
% of total
5.3%
Change from 2016
-1.3pp
486
5.3%
-1.3pp
Primary schoolers (5 to 11)
2021 count
945
% of total
10.3%
Change from 2016
+0.2pp
945
10.3%
+0.2pp
Secondary schoolers (12 to 17)
2021 count
736
% of total
8.1%
Change from 2016
+0.7pp
736
8.1%
+0.7pp
Tertiary education and independence (18 to 24)
2021 count
676
% of total
7.4%
Change from 2016
-0.4pp
676
7.4%
-0.4pp
Young workforce (25 to 34)
2021 count
1,015
% of total
11.1%
Change from 2016
+1.5pp
1,015
11.1%
+1.5pp
Parents and homebuilders (35 to 49)
2021 count
2,066
% of total
22.6%
Change from 2016
+1.7pp
2,066
22.6%
+1.7pp
Older workers and pre-retirees (50 to 59)
2021 count
1,114
% of total
12.2%
Change from 2016
-1.2pp
1,114
12.2%
-1.2pp
Empty nesters and retirees (60 to 69)
2021 count
949
% of total
10.4%
Change from 2016
-1.6pp
949
10.4%
-1.6pp
Seniors (70 to 84)
2021 count
1,038
% of total
11.4%
Change from 2016
+1.3pp
1,038
11.4%
+1.3pp
Elderly aged (85 and over)
2021 count
145
% of total
1.6%
Change from 2016
-0.3pp
145
1.6%
-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)
-40
-1.3pp
Primary schoolers (5 to 11)
+139
+0.2pp
Secondary schoolers (12 to 17)
+148
+0.7pp
Tertiary education and independence (18 to 24)
+57
-0.4pp
Young workforce (25 to 34)
+251
+1.5pp
Parents and homebuilders (35 to 49)
+399
+1.7pp
Older workers and pre-retirees (50 to 59)
+43
-1.2pp
Empty nesters and retirees (60 to 69)
-4
-1.6pp
Seniors (70 to 84)
+237
+1.3pp
Elderly aged (85 and over)
-5
-0.3pp
Data table
Service age groups for North Rocks (part). Age structure - Service age groups. 2021 and 2016 counts, percentages, and change compared with Parramatta (C).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Parramatta (C)% | Count | % | Parramatta (C)% | Count | pp | |
| Babies and pre-schoolers (0 to 4) | 486 | 5.3% | 6.2% | 526 | 6.6% | 7.3% | -40 | -1.3pp |
| Primary schoolers (5 to 11) | 945 | 10.3% | 8.8% | 806 | 10.1% | 8.2% | +139 | +0.2pp |
| Secondary schoolers (12 to 17) | 736 | 8.1% | 5.8% | 588 | 7.4% | 5.9% | +148 | +0.7pp |
| Tertiary education and independence (18 to 24) | 676 | 7.4% | 8.4% | 619 | 7.8% | 8.7% | +57 | -0.4pp |
| Young workforce (25 to 34) | 1,015 | 11.1% | 19.4% | 764 | 9.6% | 20.2% | +251 | +1.5pp |
| Parents and homebuilders (35 to 49) | 2,066 | 22.6% | 23.8% | 1,667 | 20.9% | 21.9% | +399 | +1.7pp |
| Older workers and pre-retirees (50 to 59) | 1,114 | 12.2% | 10.3% | 1,071 | 13.4% | 11.1% | +43 | -1.2pp |
| Empty nesters and retirees (60 to 69) | 949 | 10.4% | 8.6% | 953 | 12.0% | 8.4% | -4 | -1.6pp |
| Seniors (70 to 84) | 1,038 | 11.4% | 7.0% | 801 | 10.1% | 6.7% | +237 | +1.3pp |
| Elderly aged (85 and over) | 145 | 1.6% | 1.6% | 150 | 1.9% | 1.7% | -5 | -0.3pp |
| Total | 9,136 | 100.0% | 100.0% | 7,965 | 100.0% | 100.0% | +1,171 | 0.0pp |