Population

Five year age groups

About this topic

Five year age groups show the population in standard five-year cohorts from early childhood through older age. Because each band covers the same span of years, the topic gives a clear and comparable view of an area's age structure.

This topic is useful for identifying growth or decline in specific cohorts and for comparing age patterns across places and over time. For service planning, it is often read together with service age groups, household types, and dwelling types.

Interpretation notes

  • Age is reported as at Census night, so the counts are a snapshot of the resident age structure at that point in time.
  • Because each band covers the same five-year span, this topic is best for exact cohort comparison rather than service-planning life stages.

Key insight

In 2021, 25 to 29 year olds was the largest age group among residents in Sydenham (Vic.), accounting for 8.3% (883 people). This share was higher than Brimbank (C) (8.1%). Since 2016, the biggest change was in 40 to 44 year olds, which decreased by 165 people and 1.3 percentage points.

Section overview

Age structure - Five year age groups

Sydenham (Vic.) - Total persons (Usual residence)

This table summarises five year age groups for Sydenham (Vic.) in 2021 for persons, with comparison against Brimbank (C) and change since 2016.

Age structure - Five year age groups snapshot

2021 distribution by category for Sydenham (Vic.), with comparison markers for Brimbank (C).

Sydenham (Vic.)
Brimbank (C)

0 to 4

2021 count

588

% of total

5.6%

Change from 2016

-0.6pp

5 to 9

2021 count

582

% of total

5.5%

Change from 2016

-0.8pp

10 to 14

2021 count

580

% of total

5.5%

Change from 2016

-0.9pp

15 to 19

2021 count

652

% of total

6.2%

Change from 2016

-0.8pp

20 to 24

2021 count

828

% of total

7.8%

Change from 2016

-0.1pp

25 to 29

2021 count

883

% of total

8.3%

Change from 2016

-0.1pp

30 to 34

2021 count

846

% of total

8.0%

Change from 2016

0.0pp

35 to 39

2021 count

748

% of total

7.1%

Change from 2016

-0.6pp

40 to 44

2021 count

631

% of total

6.0%

Change from 2016

-1.3pp

45 to 49

2021 count

726

% of total

6.9%

Change from 2016

-0.3pp

50 to 54

2021 count

717

% of total

6.8%

Change from 2016

-0.1pp

55 to 59

2021 count

736

% of total

7.0%

Change from 2016

+1.4pp

60 to 64

2021 count

570

% of total

5.4%

Change from 2016

+1.2pp

65 to 69

2021 count

431

% of total

4.1%

Change from 2016

+1.0pp

70 to 74

2021 count

330

% of total

3.1%

Change from 2016

+0.9pp

75 to 79

2021 count

251

% of total

2.4%

Change from 2016

+0.8pp

80 to 84

2021 count

193

% of total

1.8%

Change from 2016

+0.4pp

85 and over

2021 count

285

% of total

2.7%

Change from 2016

+0.4pp

Data table

Five year age groups for Sydenham (Vic.). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Brimbank (C).

Five year age groups for Sydenham (Vic.). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Brimbank (C).
Five year age groups for Sydenham (Vic.). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Brimbank (C).
Category20212016Change
Count%Brimbank (C)%Count%Brimbank (C)%Countpp
0 to 45885.6%5.6%6756.2%6.7%-87-0.6pp
5 to 95825.5%6.0%6876.3%6.1%-105-0.8pp
10 to 145805.5%5.7%6956.4%5.7%-115-0.9pp
15 to 196526.2%5.7%7637.0%6.3%-111-0.8pp
20 to 248287.8%6.9%8597.9%7.8%-31-0.1pp
25 to 298838.3%8.1%9058.4%8.1%-22-0.1pp
30 to 348468.0%7.6%8688.0%8.0%-220.0pp
35 to 397487.1%7.2%8317.7%6.9%-83-0.6pp
40 to 446316.0%6.4%7967.3%6.6%-165-1.3pp
45 to 497266.9%6.3%7837.2%6.5%-57-0.3pp
50 to 547176.8%6.3%7506.9%6.3%-33-0.1pp
55 to 597367.0%6.1%6055.6%6.0%+131+1.4pp
60 to 645705.4%5.8%4544.2%5.4%+116+1.2pp
65 to 694314.1%5.1%3393.1%4.7%+92+1.0pp
70 to 743303.1%4.3%2352.2%3.3%+95+0.9pp
75 to 792512.4%3.0%1751.6%2.4%+76+0.8pp
80 to 841931.8%2.0%1531.4%1.7%+40+0.4pp
85 and over2852.7%1.9%2472.3%1.5%+38+0.4pp
Total10,578100.0%100.0%10,838100.0%100.0%-2600.0pp