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 Keilor Park, accounting for 7.8% (210 people). This share was higher than Brimbank (C) (6.3%). Since 2016, the biggest change was in 30 to 34 year olds, which decreased by 1,452 people and 9.1 percentage points.
Section overview
Age structure - Five year age groups
Keilor Park - Total persons (Usual residence)
This table summarises five year age groups for Keilor Park in 2021 for persons, with comparison against Brimbank (C) and change since 2016.
Age structure - Five year age groups snapshot
2021 distribution by category for Keilor Park, with comparison markers for Brimbank (C).
0 to 4
2021 count
159
% of total
5.9%
Change from 2016
-1.0pp
159
5.9%
-1.0pp
5 to 9
2021 count
180
% of total
6.7%
Change from 2016
+2.2pp
180
6.7%
+2.2pp
10 to 14
2021 count
147
% of total
5.5%
Change from 2016
+2.5pp
147
5.5%
+2.5pp
15 to 19
2021 count
117
% of total
4.4%
Change from 2016
+1.2pp
117
4.4%
+1.2pp
20 to 24
2021 count
112
% of total
4.2%
Change from 2016
-3.5pp
112
4.2%
-3.5pp
25 to 29
2021 count
140
% of total
5.2%
Change from 2016
-9.1pp
140
5.2%
-9.1pp
30 to 34
2021 count
156
% of total
5.8%
Change from 2016
-9.1pp
156
5.8%
-9.1pp
35 to 39
2021 count
167
% of total
6.2%
Change from 2016
-4.0pp
167
6.2%
-4.0pp
40 to 44
2021 count
172
% of total
6.4%
Change from 2016
-1.2pp
172
6.4%
-1.2pp
45 to 49
2021 count
210
% of total
7.8%
Change from 2016
+1.5pp
210
7.8%
+1.5pp
50 to 54
2021 count
151
% of total
5.6%
Change from 2016
+1.0pp
151
5.6%
+1.0pp
55 to 59
2021 count
127
% of total
4.7%
Change from 2016
+0.2pp
127
4.7%
+0.2pp
60 to 64
2021 count
137
% of total
5.1%
Change from 2016
+1.3pp
137
5.1%
+1.3pp
65 to 69
2021 count
135
% of total
5.0%
Change from 2016
+2.0pp
135
5.0%
+2.0pp
70 to 74
2021 count
210
% of total
7.8%
Change from 2016
+5.9pp
210
7.8%
+5.9pp
75 to 79
2021 count
178
% of total
6.6%
Change from 2016
+5.2pp
178
6.6%
+5.2pp
80 to 84
2021 count
106
% of total
3.9%
Change from 2016
+2.8pp
106
3.9%
+2.8pp
85 and over
2021 count
65
% of total
2.4%
Change from 2016
+1.4pp
65
2.4%
+1.4pp
Chart view
Age structure - Five year age groups change
Absolute change in category counts between 2016 and 2021.
0 to 4
-582
-1.0pp
5 to 9
-311
+2.2pp
10 to 14
-172
+2.5pp
15 to 19
-233
+1.2pp
20 to 24
-719
-3.5pp
25 to 29
-1,409
-9.1pp
30 to 34
-1,452
-9.1pp
35 to 39
-938
-4.0pp
40 to 44
-649
-1.2pp
45 to 49
-472
+1.5pp
50 to 54
-350
+1.0pp
55 to 59
-357
+0.2pp
60 to 64
-277
+1.3pp
65 to 69
-189
+2.0pp
70 to 74
+9
+5.9pp
75 to 79
+27
+5.2pp
80 to 84
-8
+2.8pp
85 and over
-41
+1.4pp
Data table
Five year age groups for Keilor Park. Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Brimbank (C).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Brimbank (C)% | Count | % | Brimbank (C)% | Count | pp | |
| 0 to 4 | 159 | 5.9% | 5.6% | 741 | 6.9% | 6.7% | -582 | -1.0pp |
| 5 to 9 | 180 | 6.7% | 6.0% | 491 | 4.5% | 6.1% | -311 | +2.2pp |
| 10 to 14 | 147 | 5.5% | 5.7% | 319 | 3.0% | 5.7% | -172 | +2.5pp |
| 15 to 19 | 117 | 4.4% | 5.7% | 350 | 3.2% | 6.3% | -233 | +1.2pp |
| 20 to 24 | 112 | 4.2% | 6.9% | 831 | 7.7% | 7.8% | -719 | -3.5pp |
| 25 to 29 | 140 | 5.2% | 8.1% | 1,549 | 14.3% | 8.1% | -1,409 | -9.1pp |
| 30 to 34 | 156 | 5.8% | 7.6% | 1,608 | 14.9% | 8.0% | -1,452 | -9.1pp |
| 35 to 39 | 167 | 6.2% | 7.2% | 1,105 | 10.2% | 6.9% | -938 | -4.0pp |
| 40 to 44 | 172 | 6.4% | 6.4% | 821 | 7.6% | 6.6% | -649 | -1.2pp |
| 45 to 49 | 210 | 7.8% | 6.3% | 682 | 6.3% | 6.5% | -472 | +1.5pp |
| 50 to 54 | 151 | 5.6% | 6.3% | 501 | 4.6% | 6.3% | -350 | +1.0pp |
| 55 to 59 | 127 | 4.7% | 6.1% | 484 | 4.5% | 6.0% | -357 | +0.2pp |
| 60 to 64 | 137 | 5.1% | 5.8% | 414 | 3.8% | 5.4% | -277 | +1.3pp |
| 65 to 69 | 135 | 5.0% | 5.1% | 324 | 3.0% | 4.7% | -189 | +2.0pp |
| 70 to 74 | 210 | 7.8% | 4.3% | 201 | 1.9% | 3.3% | +9 | +5.9pp |
| 75 to 79 | 178 | 6.6% | 3.0% | 151 | 1.4% | 2.4% | +27 | +5.2pp |
| 80 to 84 | 106 | 3.9% | 2.0% | 114 | 1.1% | 1.7% | -8 | +2.8pp |
| 85 and over | 65 | 2.4% | 1.9% | 106 | 1.0% | 1.5% | -41 | +1.4pp |
| Total | 2,684 | 100.0% | 100.0% | 10,812 | 100.0% | 100.0% | -8,128 | 0.0pp |