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.
Related topics
Key insight
In 2021, 45 to 49 year olds was the largest age group among residents in Willoughby (NSW), accounting for 8.6% (610 people). This share was higher than Willoughby (C) (7.7%). Since 2016, the biggest change was in 45 to 49 year olds, which increased by 610 people and 8.6 percentage points.
Section overview
Age structure - Five year age groups
Willoughby (NSW) - Total persons (Usual residence)
This table summarises five year age groups for Willoughby (NSW) in 2021 for persons, with comparison against Willoughby (C) and change since 2016.
Age structure - Five year age groups snapshot
2021 distribution by category for Willoughby (NSW), with comparison markers for Willoughby (C).
0 to 4
2021 count
429
% of total
6.0%
Change from 2016
+0.5pp
429
6.0%
+0.5pp
5 to 9
2021 count
546
% of total
7.7%
Change from 2016
-8.7pp
546
7.7%
-8.7pp
10 to 14
2021 count
518
% of total
7.3%
Change from 2016
+1.8pp
518
7.3%
+1.8pp
15 to 19
2021 count
469
% of total
6.6%
Change from 2016
+6.6pp
469
6.6%
+6.6pp
20 to 24
2021 count
298
% of total
4.2%
Change from 2016
+4.2pp
298
4.2%
+4.2pp
25 to 29
2021 count
261
% of total
3.7%
Change from 2016
+3.7pp
261
3.7%
+3.7pp
30 to 34
2021 count
341
% of total
4.8%
Change from 2016
+4.8pp
341
4.8%
+4.8pp
35 to 39
2021 count
576
% of total
8.1%
Change from 2016
+8.1pp
576
8.1%
+8.1pp
40 to 44
2021 count
600
% of total
8.4%
Change from 2016
+2.9pp
600
8.4%
+2.9pp
45 to 49
2021 count
610
% of total
8.6%
Change from 2016
+8.6pp
610
8.6%
+8.6pp
50 to 54
2021 count
542
% of total
7.6%
Change from 2016
+0.3pp
542
7.6%
+0.3pp
55 to 59
2021 count
448
% of total
6.3%
Change from 2016
-1.0pp
448
6.3%
-1.0pp
60 to 64
2021 count
356
% of total
5.0%
Change from 2016
+5.0pp
356
5.0%
+5.0pp
65 to 69
2021 count
292
% of total
4.1%
Change from 2016
+4.1pp
292
4.1%
+4.1pp
70 to 74
2021 count
261
% of total
3.7%
Change from 2016
+3.7pp
261
3.7%
+3.7pp
75 to 79
2021 count
203
% of total
2.8%
Change from 2016
+2.8pp
203
2.8%
+2.8pp
80 to 84
2021 count
146
% of total
2.0%
Change from 2016
+2.0pp
146
2.0%
+2.0pp
85 and over
2021 count
223
% of total
3.1%
Change from 2016
+3.1pp
223
3.1%
+3.1pp
Chart view
Age structure - Five year age groups change
Absolute change in category counts between 2016 and 2021.
0 to 4
+426
+0.5pp
5 to 9
+537
-8.7pp
10 to 14
+515
+1.8pp
15 to 19
+469
+6.6pp
20 to 24
+298
+4.2pp
25 to 29
+261
+3.7pp
30 to 34
+341
+4.8pp
35 to 39
+576
+8.1pp
40 to 44
+597
+2.9pp
45 to 49
+610
+8.6pp
50 to 54
+538
+0.3pp
55 to 59
+444
-1.0pp
60 to 64
+356
+5.0pp
65 to 69
+292
+4.1pp
70 to 74
+261
+3.7pp
75 to 79
+203
+2.8pp
80 to 84
+146
+2.0pp
85 and over
+223
+3.1pp
Data table
Five year age groups for Willoughby (NSW). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Willoughby (C).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Willoughby (C)% | Count | % | Willoughby (C)% | Count | pp | |
| 0 to 4 | 429 | 6.0% | 5.2% | 3 | 5.5% | 6.6% | +426 | +0.5pp |
| 5 to 9 | 546 | 7.7% | 6.8% | 9 | 16.4% | 7.0% | +537 | -8.7pp |
| 10 to 14 | 518 | 7.3% | 6.8% | 3 | 5.5% | 5.8% | +515 | +1.8pp |
| 15 to 19 | 469 | 6.6% | 5.5% | 0 | 0.0% | 5.4% | +469 | +6.6pp |
| 20 to 24 | 298 | 4.2% | 5.2% | 0 | 0.0% | 6.0% | +298 | +4.2pp |
| 25 to 29 | 261 | 3.7% | 5.8% | 0 | 0.0% | 6.9% | +261 | +3.7pp |
| 30 to 34 | 341 | 4.8% | 6.6% | 0 | 0.0% | 8.3% | +341 | +4.8pp |
| 35 to 39 | 576 | 8.1% | 8.4% | 0 | 0.0% | 8.6% | +576 | +8.1pp |
| 40 to 44 | 600 | 8.4% | 8.4% | 3 | 5.5% | 8.1% | +597 | +2.9pp |
| 45 to 49 | 610 | 8.6% | 7.7% | 0 | 0.0% | 7.2% | +610 | +8.6pp |
| 50 to 54 | 542 | 7.6% | 6.6% | 4 | 7.3% | 6.3% | +538 | +0.3pp |
| 55 to 59 | 448 | 6.3% | 5.8% | 4 | 7.3% | 5.4% | +444 | -1.0pp |
| 60 to 64 | 356 | 5.0% | 5.0% | 0 | 0.0% | 4.8% | +356 | +5.0pp |
| 65 to 69 | 292 | 4.1% | 4.5% | 0 | 0.0% | 4.4% | +292 | +4.1pp |
| 70 to 74 | 261 | 3.7% | 4.1% | 0 | 0.0% | 2.9% | +261 | +3.7pp |
| 75 to 79 | 203 | 2.8% | 2.8% | 0 | 0.0% | 2.2% | +203 | +2.8pp |
| 80 to 84 | 146 | 2.0% | 2.0% | 0 | 0.0% | 1.8% | +146 | +2.0pp |
| 85 and over | 223 | 3.1% | 2.6% | 0 | 0.0% | 2.3% | +223 | +3.1pp |
| Total | 7,124 | 100.0% | 100.0% | 55 | 100.0% | 100.0% | +7,069 | 0.0pp |