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 Bacchus Marsh, accounting for 17.8% (1,387 people). This share was lower than Moorabool (S) (20.2%). Since 2016, the biggest change was in Young workforce (25 to 34), which increased by 495 people and 4.4 percentage points.
Section overview
Age structure - Service age groups
Bacchus Marsh - Total persons (Usual residence)
This table summarises service age groups for Bacchus Marsh in 2021 for persons, with comparison against Moorabool (S) and change since 2016.
Age structure - Service age groups snapshot
2021 distribution by category for Bacchus Marsh, with comparison markers for Moorabool (S).
Babies and pre-schoolers (0 to 4)
2021 count
498
% of total
6.4%
Change from 2016
+0.7pp
498
6.4%
+0.7pp
Primary schoolers (5 to 11)
2021 count
698
% of total
8.9%
Change from 2016
+0.1pp
698
8.9%
+0.1pp
Secondary schoolers (12 to 17)
2021 count
494
% of total
6.3%
Change from 2016
-0.3pp
494
6.3%
-0.3pp
Tertiary education and independence (18 to 24)
2021 count
540
% of total
6.9%
Change from 2016
-1.1pp
540
6.9%
-1.1pp
Young workforce (25 to 34)
2021 count
1,193
% of total
15.3%
Change from 2016
+4.4pp
1,193
15.3%
+4.4pp
Parents and homebuilders (35 to 49)
2021 count
1,387
% of total
17.8%
Change from 2016
-0.4pp
1,387
17.8%
-0.4pp
Older workers and pre-retirees (50 to 59)
2021 count
852
% of total
10.9%
Change from 2016
-1.9pp
852
10.9%
-1.9pp
Empty nesters and retirees (60 to 69)
2021 count
873
% of total
11.2%
Change from 2016
-1.9pp
873
11.2%
-1.9pp
Seniors (70 to 84)
2021 count
1,095
% of total
14.0%
Change from 2016
+0.9pp
1,095
14.0%
+0.9pp
Elderly aged (85 and over)
2021 count
174
% of total
2.2%
Change from 2016
-0.6pp
174
2.2%
-0.6pp
Chart view
Age structure - Service age groups change
Absolute change in category counts between 2016 and 2021.
Babies and pre-schoolers (0 to 4)
+132
+0.7pp
Primary schoolers (5 to 11)
+135
+0.1pp
Secondary schoolers (12 to 17)
+72
-0.3pp
Tertiary education and independence (18 to 24)
+26
-1.1pp
Young workforce (25 to 34)
+495
+4.4pp
Parents and homebuilders (35 to 49)
+222
-0.4pp
Older workers and pre-retirees (50 to 59)
+36
-1.9pp
Empty nesters and retirees (60 to 69)
+34
-1.9pp
Seniors (70 to 84)
+259
+0.9pp
Elderly aged (85 and over)
-4
-0.6pp
Data table
Service age groups for Bacchus Marsh. Age structure - Service age groups. 2021 and 2016 counts, percentages, and change compared with Moorabool (S).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Moorabool (S)% | Count | % | Moorabool (S)% | Count | pp | |
| Babies and pre-schoolers (0 to 4) | 498 | 6.4% | 6.3% | 366 | 5.7% | 6.4% | +132 | +0.7pp |
| Primary schoolers (5 to 11) | 698 | 8.9% | 9.6% | 563 | 8.8% | 10.0% | +135 | +0.1pp |
| Secondary schoolers (12 to 17) | 494 | 6.3% | 7.8% | 422 | 6.6% | 7.9% | +72 | -0.3pp |
| Tertiary education and independence (18 to 24) | 540 | 6.9% | 7.2% | 514 | 8.0% | 7.9% | +26 | -1.1pp |
| Young workforce (25 to 34) | 1,193 | 15.3% | 12.7% | 698 | 10.9% | 11.0% | +495 | +4.4pp |
| Parents and homebuilders (35 to 49) | 1,387 | 17.8% | 20.2% | 1,165 | 18.2% | 20.9% | +222 | -0.4pp |
| Older workers and pre-retirees (50 to 59) | 852 | 10.9% | 13.3% | 816 | 12.8% | 14.2% | +36 | -1.9pp |
| Empty nesters and retirees (60 to 69) | 873 | 11.2% | 11.3% | 839 | 13.1% | 12.0% | +34 | -1.9pp |
| Seniors (70 to 84) | 1,095 | 14.0% | 10.0% | 836 | 13.1% | 8.2% | +259 | +0.9pp |
| Elderly aged (85 and over) | 174 | 2.2% | 1.7% | 178 | 2.8% | 1.5% | -4 | -0.6pp |
| Total | 7,808 | 100.0% | 100.0% | 6,394 | 100.0% | 100.0% | +1,414 | 0.0pp |