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, 50 to 54 year olds was the largest age group among residents in Cottesloe (T), accounting for 8% (634 people). This share was higher than Greater Perth (6.4%). Since 2016, the biggest change was in 75 to 79 year olds, which increased by 159 people and 1.8 percentage points.

Section overview

Age structure - Five year age groups

Cottesloe (T) - Total persons (Usual residence)

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

Age structure - Five year age groups change

Absolute change in category counts between 2016 and 2021.

2016
2021

0 to 4

+8

-0.1pp

5 to 9

-73

-1.2pp

10 to 14

-34

-0.7pp

15 to 19

+107

+1.1pp

20 to 24

+57

+0.5pp

25 to 29

-20

-0.6pp

30 to 34

-38

-0.7pp

35 to 39

-1

-0.3pp

40 to 44

+15

-0.1pp

45 to 49

-114

-1.8pp

50 to 54

+84

+0.8pp

55 to 59

+13

-0.2pp

60 to 64

+30

+0.1pp

65 to 69

+55

+0.4pp

70 to 74

+92

+0.9pp

75 to 79

+159

+1.8pp

80 to 84

+58

+0.7pp

85 and over

-11

-0.3pp

Data table

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

Five year age groups for Cottesloe (T). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Greater Perth.
Five year age groups for Cottesloe (T). 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 43524.4%6.1%3444.5%6.5%+8-0.1pp
5 to 93904.9%6.4%4636.1%6.5%-73-1.2pp
10 to 145086.4%6.4%5427.1%6.0%-34-0.7pp
15 to 195667.1%5.8%4596.0%6.2%+107+1.1pp
20 to 244605.8%6.3%4035.3%6.9%+57+0.5pp
25 to 294806.0%6.8%5006.6%7.7%-20-0.6pp
30 to 344285.4%7.6%4666.1%8.0%-38-0.7pp
35 to 394145.2%7.7%4155.5%7.1%-1-0.3pp
40 to 444345.4%6.8%4195.5%6.9%+15-0.1pp
45 to 494695.9%6.5%5837.7%6.9%-114-1.8pp
50 to 546348.0%6.4%5507.2%6.4%+84+0.8pp
55 to 595797.3%5.9%5667.5%5.8%+13-0.2pp
60 to 645406.8%5.4%5106.7%5.1%+30+0.1pp
65 to 694986.2%4.8%4435.8%4.6%+55+0.4pp
70 to 744645.8%4.2%3724.9%3.3%+92+0.9pp
75 to 793784.7%2.9%2192.9%2.5%+159+1.8pp
80 to 841982.5%2.0%1401.8%1.7%+58+0.7pp
85 and over2182.7%1.9%2293.0%1.8%-11-0.3pp
Total7,970100.0%100.0%7,597100.0%100.0%+3730.0pp