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, 50 to 54 year olds was the largest age group among residents in Bayside (C), accounting for 8.3% (8,451 people). This share was higher than Greater Melbourne (6.3%). Since 2016, the biggest change was in 75 to 79 year olds, which increased by 1,154 people and 1 percentage point.
Section overview
Age structure - Five year age groups
Bayside (C) - Total persons (Usual residence)
This table summarises five year age groups for Bayside (C) in 2021 for persons, with comparison against Greater Melbourne and change since 2016.
Chart view
Age structure - Five year age groups snapshot
2021 distribution by category for Bayside (C), with comparison markers for Greater Melbourne.
0 to 4
2021 count
4,443
% of total
4.4%
Change from 2016
-0.7pp
4,443
4.4%
-0.7pp
5 to 9
2021 count
5,911
% of total
5.8%
Change from 2016
-1.0pp
5,911
5.8%
-1.0pp
10 to 14
2021 count
7,310
% of total
7.2%
Change from 2016
+0.1pp
7,310
7.2%
+0.1pp
15 to 19
2021 count
6,961
% of total
6.9%
Change from 2016
+0.5pp
6,961
6.9%
+0.5pp
20 to 24
2021 count
5,209
% of total
5.1%
Change from 2016
0.0pp
5,209
5.1%
0.0pp
25 to 29
2021 count
3,665
% of total
3.6%
Change from 2016
-0.3pp
3,665
3.6%
-0.3pp
30 to 34
2021 count
4,249
% of total
4.2%
Change from 2016
-0.1pp
4,249
4.2%
-0.1pp
35 to 39
2021 count
5,407
% of total
5.3%
Change from 2016
-0.1pp
5,407
5.3%
-0.1pp
40 to 44
2021 count
6,398
% of total
6.3%
Change from 2016
-1.1pp
6,398
6.3%
-1.1pp
45 to 49
2021 count
7,799
% of total
7.7%
Change from 2016
-0.9pp
7,799
7.7%
-0.9pp
50 to 54
2021 count
8,451
% of total
8.3%
Change from 2016
+0.5pp
8,451
8.3%
+0.5pp
55 to 59
2021 count
7,414
% of total
7.3%
Change from 2016
+0.2pp
7,414
7.3%
+0.2pp
60 to 64
2021 count
6,624
% of total
6.5%
Change from 2016
+0.6pp
6,624
6.5%
+0.6pp
65 to 69
2021 count
5,626
% of total
5.6%
Change from 2016
0.0pp
5,626
5.6%
0.0pp
70 to 74
2021 count
5,451
% of total
5.4%
Change from 2016
+1.0pp
5,451
5.4%
+1.0pp
75 to 79
2021 count
4,176
% of total
4.1%
Change from 2016
+1.0pp
4,176
4.1%
+1.0pp
80 to 84
2021 count
2,760
% of total
2.7%
Change from 2016
+0.3pp
2,760
2.7%
+0.3pp
85 and over
2021 count
3,423
% of total
3.4%
Change from 2016
-0.3pp
3,423
3.4%
-0.3pp
Age structure - Five year age groups change
Absolute change in category counts between 2016 and 2021.
0 to 4
-548
-0.7pp
5 to 9
-668
-1.0pp
10 to 14
+465
+0.1pp
15 to 19
+780
+0.5pp
20 to 24
+291
0.0pp
25 to 29
-88
-0.3pp
30 to 34
+30
-0.1pp
35 to 39
+142
-0.1pp
40 to 44
-756
-1.1pp
45 to 49
-516
-0.9pp
50 to 54
+909
+0.5pp
55 to 59
+534
+0.2pp
60 to 64
+870
+0.6pp
65 to 69
+229
0.0pp
70 to 74
+1,144
+1.0pp
75 to 79
+1,154
+1.0pp
80 to 84
+438
+0.3pp
85 and over
-200
-0.3pp
Data table
Five year age groups for Bayside (C). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Greater Melbourne.
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Greater Melbourne% | Count | % | Greater Melbourne% | Count | pp | |
| 0 to 4 | 4,443 | 4.4% | 5.9% | 4,991 | 5.1% | 6.4% | -548 | -0.7pp |
| 5 to 9 | 5,911 | 5.8% | 6.3% | 6,579 | 6.8% | 6.2% | -668 | -1.0pp |
| 10 to 14 | 7,310 | 7.2% | 6.0% | 6,845 | 7.1% | 5.7% | +465 | +0.1pp |
| 15 to 19 | 6,961 | 6.9% | 5.6% | 6,181 | 6.4% | 6.0% | +780 | +0.5pp |
| 20 to 24 | 5,209 | 5.1% | 6.7% | 4,918 | 5.1% | 7.4% | +291 | 0.0pp |
| 25 to 29 | 3,665 | 3.6% | 7.8% | 3,753 | 3.9% | 8.1% | -88 | -0.3pp |
| 30 to 34 | 4,249 | 4.2% | 8.2% | 4,219 | 4.3% | 8.2% | +30 | -0.1pp |
| 35 to 39 | 5,407 | 5.3% | 8.0% | 5,265 | 5.4% | 7.3% | +142 | -0.1pp |
| 40 to 44 | 6,398 | 6.3% | 6.9% | 7,154 | 7.4% | 7.0% | -756 | -1.1pp |
| 45 to 49 | 7,799 | 7.7% | 6.5% | 8,315 | 8.6% | 6.9% | -516 | -0.9pp |
| 50 to 54 | 8,451 | 8.3% | 6.3% | 7,542 | 7.8% | 6.2% | +909 | +0.5pp |
| 55 to 59 | 7,414 | 7.3% | 5.7% | 6,880 | 7.1% | 5.7% | +534 | +0.2pp |
| 60 to 64 | 6,624 | 6.5% | 5.1% | 5,754 | 5.9% | 4.9% | +870 | +0.6pp |
| 65 to 69 | 5,626 | 5.6% | 4.4% | 5,397 | 5.6% | 4.4% | +229 | 0.0pp |
| 70 to 74 | 5,451 | 5.4% | 3.9% | 4,307 | 4.4% | 3.3% | +1,144 | +1.0pp |
| 75 to 79 | 4,176 | 4.1% | 2.8% | 3,022 | 3.1% | 2.5% | +1,154 | +1.0pp |
| 80 to 84 | 2,760 | 2.7% | 2.0% | 2,322 | 2.4% | 1.9% | +438 | +0.3pp |
| 85 and over | 3,423 | 3.4% | 2.0% | 3,623 | 3.7% | 2.0% | -200 | -0.3pp |
| Total | 101,306 | 100.0% | 100.0% | 97,087 | 100.0% | 100.0% | +4,219 | 0.0pp |