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, 10 to 14 year olds was the largest age group among residents in Rockingham (C), accounting for 7.6% (10,330 people). This share was higher than Greater Perth (6.4%). Since 2016, the biggest change was in 10 to 14 year olds, which increased by 1,682 people and 0.7 percentage points.

Section overview

Age structure - Five year age groups

Rockingham (C) - Total persons (Usual residence)

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

Age structure - Five year age groups snapshot

2021 distribution by category for Rockingham (C), with comparison markers for Greater Perth.

Rockingham (C)
Greater Perth

0 to 4

2021 count

9,154

% of total

6.7%

Change from 2016

-0.8pp

5 to 9

2021 count

9,952

% of total

7.3%

Change from 2016

-0.6pp

10 to 14

2021 count

10,330

% of total

7.6%

Change from 2016

+0.7pp

15 to 19

2021 count

8,790

% of total

6.5%

Change from 2016

-0.1pp

20 to 24

2021 count

8,100

% of total

6.0%

Change from 2016

-0.8pp

25 to 29

2021 count

8,712

% of total

6.4%

Change from 2016

-0.8pp

30 to 34

2021 count

9,620

% of total

7.1%

Change from 2016

-0.3pp

35 to 39

2021 count

9,676

% of total

7.1%

Change from 2016

+0.4pp

40 to 44

2021 count

8,707

% of total

6.4%

Change from 2016

-0.7pp

45 to 49

2021 count

8,912

% of total

6.6%

Change from 2016

-0.5pp

50 to 54

2021 count

8,975

% of total

6.6%

Change from 2016

-0.1pp

55 to 59

2021 count

8,435

% of total

6.2%

Change from 2016

+0.7pp

60 to 64

2021 count

7,120

% of total

5.2%

Change from 2016

+0.7pp

65 to 69

2021 count

5,827

% of total

4.3%

Change from 2016

+0.3pp

70 to 74

2021 count

5,070

% of total

3.7%

Change from 2016

+0.6pp

75 to 79

2021 count

3,752

% of total

2.8%

Change from 2016

+0.5pp

80 to 84

2021 count

2,460

% of total

1.8%

Change from 2016

+0.2pp

85 and over

2021 count

2,083

% of total

1.5%

Change from 2016

+0.1pp

Data table

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

Five year age groups for Rockingham (C). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Greater Perth.
Five year age groups for Rockingham (C). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Greater Perth.
Category20212016Change
Count%Greater Perth%Count%Greater Perth%Countpp
0 to 49,1546.7%6.1%9,4117.5%6.5%-257-0.8pp
5 to 99,9527.3%6.4%9,8617.9%6.5%+91-0.6pp
10 to 1410,3307.6%6.4%8,6486.9%6.0%+1,682+0.7pp
15 to 198,7906.5%5.8%8,2066.6%6.2%+584-0.1pp
20 to 248,1006.0%6.3%8,5076.8%6.9%-407-0.8pp
25 to 298,7126.4%6.8%8,9957.2%7.7%-283-0.8pp
30 to 349,6207.1%7.6%9,2287.4%8.0%+392-0.3pp
35 to 399,6767.1%7.7%8,3656.7%7.1%+1,311+0.4pp
40 to 448,7076.4%6.8%8,8307.1%6.9%-123-0.7pp
45 to 498,9126.6%6.5%8,8637.1%6.9%+49-0.5pp
50 to 548,9756.6%6.4%8,3496.7%6.4%+626-0.1pp
55 to 598,4356.2%5.9%6,8295.5%5.8%+1,606+0.7pp
60 to 647,1205.2%5.4%5,5834.5%5.1%+1,537+0.7pp
65 to 695,8274.3%4.8%4,9444.0%4.6%+883+0.3pp
70 to 745,0703.7%4.2%3,9133.1%3.3%+1,157+0.6pp
75 to 793,7522.8%2.9%2,8982.3%2.5%+854+0.5pp
80 to 842,4601.8%2.0%1,9681.6%1.7%+492+0.2pp
85 and over2,0831.5%1.9%1,7081.4%1.8%+375+0.1pp
Total135,678100.0%100.0%125,114100.0%100.0%+10,5640.0pp