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.

Key insight

In 2021, Parents and homebuilders (35 to 49) was the most common category among residents in O'Halloran Hill (part), accounting for 19.5% (530 people). This share was higher than Onkaparinga (C) (19.2%). Since 2016, the biggest change was in Parents and homebuilders (35 to 49), which increased by 245 people, while its share fell by 0.2 percentage points.

Section overview

Age structure - Service age groups

O'Halloran Hill (part) - Total persons (Usual residence)

This table summarises service age groups for O'Halloran Hill (part) in 2021 for persons, with comparison against Onkaparinga (C) and change since 2016.

Age structure - Service age groups snapshot

2021 distribution by category for O'Halloran Hill (part), with comparison markers for Onkaparinga (C).

O'Halloran Hill (part)
Onkaparinga (C)

Babies and pre-schoolers (0 to 4)

2021 count

144

% of total

5.3%

Change from 2016

-2.0pp

Primary schoolers (5 to 11)

2021 count

227

% of total

8.3%

Change from 2016

-2.2pp

Secondary schoolers (12 to 17)

2021 count

185

% of total

6.8%

Change from 2016

+0.9pp

Tertiary education and independence (18 to 24)

2021 count

185

% of total

6.8%

Change from 2016

-1.1pp

Young workforce (25 to 34)

2021 count

404

% of total

14.8%

Change from 2016

+2.1pp

Parents and homebuilders (35 to 49)

2021 count

530

% of total

19.5%

Change from 2016

-0.2pp

Older workers and pre-retirees (50 to 59)

2021 count

348

% of total

12.8%

Change from 2016

-1.3pp

Empty nesters and retirees (60 to 69)

2021 count

295

% of total

10.8%

Change from 2016

-3.1pp

Seniors (70 to 84)

2021 count

336

% of total

12.3%

Change from 2016

+3.9pp

Elderly aged (85 and over)

2021 count

24

% of total

0.9%

Change from 2016

-0.2pp

Data table

Service age groups for O'Halloran Hill (part). Age structure - Service age groups. 2021 and 2016 counts, percentages, and change compared with Onkaparinga (C).

Service age groups for O'Halloran Hill (part). Age structure - Service age groups. 2021 and 2016 counts, percentages, and change compared with Onkaparinga (C).
Service age groups for O'Halloran Hill (part). Age structure - Service age groups. 2021 and 2016 counts, percentages, and change compared with Onkaparinga (C).
Category20212016Change
Count%Onkaparinga (C)%Count%Onkaparinga (C)%Countpp
Babies and pre-schoolers (0 to 4)1445.3%5.4%1067.3%6.2%+38-2.0pp
Primary schoolers (5 to 11)2278.3%8.6%15210.5%8.9%+75-2.2pp
Secondary schoolers (12 to 17)1856.8%7.3%865.9%7.5%+99+0.9pp
Tertiary education and independence (18 to 24)1856.8%7.9%1157.9%8.4%+70-1.1pp
Young workforce (25 to 34)40414.8%12.2%18412.7%12.4%+220+2.1pp
Parents and homebuilders (35 to 49)53019.5%19.2%28519.7%19.7%+245-0.2pp
Older workers and pre-retirees (50 to 59)34812.8%13.1%20514.1%13.3%+143-1.3pp
Empty nesters and retirees (60 to 69)29510.8%12.3%20113.9%12.4%+94-3.1pp
Seniors (70 to 84)33612.3%11.8%1218.4%9.1%+215+3.9pp
Elderly aged (85 and over)240.9%2.2%161.1%2.1%+8-0.2pp
Total2,722100.0%100.0%1,449100.0%100.0%+1,2730.0pp