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 Smithfield Plains, accounting for 18.9% (625 people). This share was higher than Playford (C) (18.5%). Since 2016, the biggest change was in Parents and homebuilders (35 to 49), which increased by 114 people and 1.1 percentage points.
Section overview
Age structure - Service age groups
Smithfield Plains - Total persons (Usual residence)
This table summarises service age groups for Smithfield Plains in 2021 for persons, with comparison against Playford (C) and change since 2016.
Age structure - Service age groups snapshot
2021 distribution by category for Smithfield Plains, with comparison markers for Playford (C).
Babies and pre-schoolers (0 to 4)
2021 count
279
% of total
8.4%
Change from 2016
-2.0pp
279
8.4%
-2.0pp
Primary schoolers (5 to 11)
2021 count
431
% of total
13.0%
Change from 2016
+0.6pp
431
13.0%
+0.6pp
Secondary schoolers (12 to 17)
2021 count
308
% of total
9.3%
Change from 2016
+0.9pp
308
9.3%
+0.9pp
Tertiary education and independence (18 to 24)
2021 count
326
% of total
9.9%
Change from 2016
-1.2pp
326
9.9%
-1.2pp
Young workforce (25 to 34)
2021 count
580
% of total
17.5%
Change from 2016
0.0pp
580
17.5%
0.0pp
Parents and homebuilders (35 to 49)
2021 count
625
% of total
18.9%
Change from 2016
+1.1pp
625
18.9%
+1.1pp
Older workers and pre-retirees (50 to 59)
2021 count
321
% of total
9.7%
Change from 2016
-0.2pp
321
9.7%
-0.2pp
Empty nesters and retirees (60 to 69)
2021 count
239
% of total
7.2%
Change from 2016
-0.6pp
239
7.2%
-0.6pp
Seniors (70 to 84)
2021 count
190
% of total
5.7%
Change from 2016
+0.7pp
190
5.7%
+0.7pp
Elderly aged (85 and over)
2021 count
24
% of total
0.7%
Change from 2016
+0.2pp
24
0.7%
+0.2pp
Chart view
Age structure - Service age groups change
Absolute change in category counts between 2016 and 2021.
Babies and pre-schoolers (0 to 4)
-19
-2.0pp
Primary schoolers (5 to 11)
+75
+0.6pp
Secondary schoolers (12 to 17)
+66
+0.9pp
Tertiary education and independence (18 to 24)
+7
-1.2pp
Young workforce (25 to 34)
+76
0.0pp
Parents and homebuilders (35 to 49)
+114
+1.1pp
Older workers and pre-retirees (50 to 59)
+36
-0.2pp
Empty nesters and retirees (60 to 69)
+16
-0.6pp
Seniors (70 to 84)
+47
+0.7pp
Elderly aged (85 and over)
+9
+0.2pp
Data table
Service age groups for Smithfield Plains. 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) | 279 | 8.4% | 7.5% | 298 | 10.4% | 8.6% | -19 | -2.0pp |
| Primary schoolers (5 to 11) | 431 | 13.0% | 11.0% | 356 | 12.4% | 10.6% | +75 | +0.6pp |
| Secondary schoolers (12 to 17) | 308 | 9.3% | 8.1% | 242 | 8.4% | 7.8% | +66 | +0.9pp |
| Tertiary education and independence (18 to 24) | 326 | 9.9% | 9.5% | 319 | 11.1% | 10.5% | +7 | -1.2pp |
| Young workforce (25 to 34) | 580 | 17.5% | 15.9% | 504 | 17.5% | 15.3% | +76 | 0.0pp |
| Parents and homebuilders (35 to 49) | 625 | 18.9% | 18.5% | 511 | 17.8% | 18.2% | +114 | +1.1pp |
| Older workers and pre-retirees (50 to 59) | 321 | 9.7% | 11.6% | 285 | 9.9% | 12.3% | +36 | -0.2pp |
| Empty nesters and retirees (60 to 69) | 239 | 7.2% | 9.1% | 223 | 7.8% | 8.4% | +16 | -0.6pp |
| Seniors (70 to 84) | 190 | 5.7% | 7.2% | 143 | 5.0% | 6.9% | +47 | +0.7pp |
| Elderly aged (85 and over) | 24 | 0.7% | 1.6% | 15 | 0.5% | 1.5% | +9 | +0.2pp |
| Total | 3,305 | 100.0% | 100.0% | 2,873 | 100.0% | 100.0% | +432 | 0.0pp |