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 Karratha (C), accounting for 10.8% (2,398 people). This share was higher than Regional WA (6.8%). Since 2016, the biggest change was in 35 to 39 year olds, which increased by 345 people and 1.2 percentage points.

Section overview

Age structure - Five year age groups

Karratha (C) - Total persons (Usual residence)

This table summarises five year age groups for Karratha (C) in 2021 for persons, with comparison against Regional WA 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

-161

-1.0pp

5 to 9

+194

+0.6pp

10 to 14

+300

+1.1pp

15 to 19

+106

+0.3pp

20 to 24

-164

-0.9pp

25 to 29

-263

-1.5pp

30 to 34

-209

-1.3pp

35 to 39

+345

+1.2pp

40 to 44

-1

-0.3pp

45 to 49

+101

+0.2pp

50 to 54

+28

0.0pp

55 to 59

+64

+0.1pp

60 to 64

+175

+0.7pp

65 to 69

+75

+0.3pp

70 to 74

+79

+0.3pp

75 to 79

+12

0.0pp

80 to 84

+33

+0.2pp

85 and over

-21

-0.1pp

Data table

Five year age groups for Karratha (C). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Regional WA.

Five year age groups for Karratha (C). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Regional WA.
Five year age groups for Karratha (C). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Regional WA.
Category20212016Change
Count%Regional WA%Count%Regional WA%Countpp
0 to 41,8778.5%6.0%2,0389.5%6.6%-161-1.0pp
5 to 92,0489.2%6.7%1,8548.6%7.1%+194+0.6pp
10 to 141,7147.7%6.7%1,4146.6%6.5%+300+1.1pp
15 to 191,1995.4%5.5%1,0935.1%5.7%+106+0.3pp
20 to 241,1675.3%4.8%1,3316.2%5.0%-164-0.9pp
25 to 291,8098.1%5.9%2,0729.6%6.5%-263-1.5pp
30 to 342,30310.4%6.6%2,51211.7%7.1%-209-1.3pp
35 to 392,39810.8%6.8%2,0539.6%6.7%+345+1.2pp
40 to 441,9408.7%6.4%1,9419.0%7.0%-1-0.3pp
45 to 491,7517.9%6.6%1,6507.7%7.2%+101+0.2pp
50 to 541,3906.3%6.9%1,3626.3%7.1%+280.0pp
55 to 591,0684.8%6.8%1,0044.7%6.9%+64+0.1pp
60 to 647953.6%6.7%6202.9%6.0%+175+0.7pp
65 to 693841.7%5.7%3091.4%5.3%+75+0.3pp
70 to 741980.9%4.9%1190.6%3.6%+79+0.3pp
75 to 79760.3%3.2%640.3%2.6%+120.0pp
80 to 84560.3%2.0%230.1%1.6%+33+0.2pp
85 and over50.0%1.7%260.1%1.5%-21-0.1pp
Total22,199100.0%100.0%21,473100.0%100.0%+7260.0pp