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, 35 to 39 year olds was the largest age group among residents in Knox (C), accounting for 7.2% (11,392 people). This share was lower than Greater Melbourne (8%). Since 2016, the biggest change was in 70 to 74 year olds, which increased by 1,779 people and 1 percentage point.

Section overview

Age structure - Five year age groups

Knox (C) - Total persons (Usual residence)

This table summarises five year age groups for Knox (C) in 2021 for persons, with comparison against Greater Melbourne and change since 2016.

Age structure - Five year age groups snapshot

2021 distribution by category for Knox (C), with comparison markers for Greater Melbourne.

Knox (C)
Greater Melbourne

0 to 4

2021 count

8,431

% of total

5.3%

Change from 2016

-0.6pp

5 to 9

2021 count

9,401

% of total

5.9%

Change from 2016

0.0pp

10 to 14

2021 count

9,276

% of total

5.8%

Change from 2016

0.0pp

15 to 19

2021 count

9,316

% of total

5.9%

Change from 2016

-0.5pp

20 to 24

2021 count

9,662

% of total

6.1%

Change from 2016

-0.5pp

25 to 29

2021 count

9,527

% of total

6.0%

Change from 2016

-0.4pp

30 to 34

2021 count

10,699

% of total

6.7%

Change from 2016

-0.1pp

35 to 39

2021 count

11,392

% of total

7.2%

Change from 2016

+0.5pp

40 to 44

2021 count

10,886

% of total

6.8%

Change from 2016

0.0pp

45 to 49

2021 count

10,694

% of total

6.7%

Change from 2016

-0.5pp

50 to 54

2021 count

10,857

% of total

6.8%

Change from 2016

-0.4pp

55 to 59

2021 count

10,612

% of total

6.7%

Change from 2016

-0.1pp

60 to 64

2021 count

9,909

% of total

6.2%

Change from 2016

+0.1pp

65 to 69

2021 count

8,618

% of total

5.4%

Change from 2016

+0.2pp

70 to 74

2021 count

7,383

% of total

4.6%

Change from 2016

+1.0pp

75 to 79

2021 count

5,164

% of total

3.2%

Change from 2016

+0.5pp

80 to 84

2021 count

3,742

% of total

2.4%

Change from 2016

+0.5pp

85 and over

2021 count

3,543

% of total

2.2%

Change from 2016

+0.2pp

Data table

Five year age groups for Knox (C). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Greater Melbourne.

Five year age groups for Knox (C). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Greater Melbourne.
Five year age groups for Knox (C). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Greater Melbourne.
Category20212016Change
Count%Greater Melbourne%Count%Greater Melbourne%Countpp
0 to 48,4315.3%5.9%9,0185.9%6.4%-587-0.6pp
5 to 99,4015.9%6.3%9,0595.9%6.2%+3420.0pp
10 to 149,2765.8%6.0%8,9755.8%5.7%+3010.0pp
15 to 199,3165.9%5.6%9,9086.4%6.0%-592-0.5pp
20 to 249,6626.1%6.7%10,2066.6%7.4%-544-0.5pp
25 to 299,5276.0%7.8%9,9156.4%8.1%-388-0.4pp
30 to 3410,6996.7%8.2%10,4166.8%8.2%+283-0.1pp
35 to 3911,3927.2%8.0%10,2826.7%7.3%+1,110+0.5pp
40 to 4410,8866.8%6.9%10,4736.8%7.0%+4130.0pp
45 to 4910,6946.7%6.5%11,0507.2%6.9%-356-0.5pp
50 to 5410,8576.8%6.3%11,0277.2%6.2%-170-0.4pp
55 to 5910,6126.7%5.7%10,4936.8%5.7%+119-0.1pp
60 to 649,9096.2%5.1%9,3976.1%4.9%+512+0.1pp
65 to 698,6185.4%4.4%8,0635.2%4.4%+555+0.2pp
70 to 747,3834.6%3.9%5,6043.6%3.3%+1,779+1.0pp
75 to 795,1643.2%2.8%4,2272.7%2.5%+937+0.5pp
80 to 843,7422.4%2.0%2,8871.9%1.9%+855+0.5pp
85 and over3,5432.2%2.0%3,1062.0%2.0%+437+0.2pp
Total159,103100.0%100.0%154,110100.0%100.0%+4,9930.0pp