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, 5 to 9 year olds was the largest age group among residents in Two Rocks, accounting for 8.3% (319 people). This share was higher than Wanneroo (C) (7.6%). Since 2016, the biggest change was in 50 to 54 year olds, which increased by 160 people and 1.9 percentage points.
Section overview
Age structure - Five year age groups
Two Rocks - Total persons (Usual residence)
This table summarises five year age groups for Two Rocks in 2021 for persons, with comparison against Wanneroo (C) and change since 2016.
Age structure - Five year age groups snapshot
2021 distribution by category for Two Rocks, with comparison markers for Wanneroo (C).
0 to 4
2021 count
253
% of total
6.6%
Change from 2016
-1.8pp
253
6.6%
-1.8pp
5 to 9
2021 count
319
% of total
8.3%
Change from 2016
-1.7pp
319
8.3%
-1.7pp
10 to 14
2021 count
308
% of total
8.1%
Change from 2016
-0.8pp
308
8.1%
-0.8pp
15 to 19
2021 count
199
% of total
5.2%
Change from 2016
-1.7pp
199
5.2%
-1.7pp
20 to 24
2021 count
177
% of total
4.6%
Change from 2016
-0.1pp
177
4.6%
-0.1pp
25 to 29
2021 count
182
% of total
4.8%
Change from 2016
+0.1pp
182
4.8%
+0.1pp
30 to 34
2021 count
249
% of total
6.5%
Change from 2016
-1.0pp
249
6.5%
-1.0pp
35 to 39
2021 count
233
% of total
6.1%
Change from 2016
-1.7pp
233
6.1%
-1.7pp
40 to 44
2021 count
248
% of total
6.5%
Change from 2016
-2.3pp
248
6.5%
-2.3pp
45 to 49
2021 count
255
% of total
6.7%
Change from 2016
+1.1pp
255
6.7%
+1.1pp
50 to 54
2021 count
315
% of total
8.2%
Change from 2016
+1.9pp
315
8.2%
+1.9pp
55 to 59
2021 count
250
% of total
6.5%
Change from 2016
-0.1pp
250
6.5%
-0.1pp
60 to 64
2021 count
270
% of total
7.1%
Change from 2016
+1.4pp
270
7.1%
+1.4pp
65 to 69
2021 count
193
% of total
5.0%
Change from 2016
+0.2pp
193
5.0%
+0.2pp
70 to 74
2021 count
176
% of total
4.6%
Change from 2016
+1.6pp
176
4.6%
+1.6pp
75 to 79
2021 count
104
% of total
2.7%
Change from 2016
+1.4pp
104
2.7%
+1.4pp
80 to 84
2021 count
73
% of total
1.9%
Change from 2016
+1.2pp
73
1.9%
+1.2pp
85 and over
2021 count
34
% of total
0.9%
Change from 2016
+0.7pp
34
0.9%
+0.7pp
Chart view
Age structure - Five year age groups change
Absolute change in category counts between 2016 and 2021.
0 to 4
+45
-1.8pp
5 to 9
+70
-1.7pp
10 to 14
+87
-0.8pp
15 to 19
+28
-1.7pp
20 to 24
+61
-0.1pp
25 to 29
+65
+0.1pp
30 to 34
+63
-1.0pp
35 to 39
+39
-1.7pp
40 to 44
+29
-2.3pp
45 to 49
+116
+1.1pp
50 to 54
+160
+1.9pp
55 to 59
+87
-0.1pp
60 to 64
+129
+1.4pp
65 to 69
+75
+0.2pp
70 to 74
+101
+1.6pp
75 to 79
+72
+1.4pp
80 to 84
+55
+1.2pp
85 and over
+29
+0.7pp
Data table
Five year age groups for Two Rocks. Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Wanneroo (C).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Wanneroo (C)% | Count | % | Wanneroo (C)% | Count | pp | |
| 0 to 4 | 253 | 6.6% | 7.1% | 208 | 8.4% | 8.0% | +45 | -1.8pp |
| 5 to 9 | 319 | 8.3% | 7.6% | 249 | 10.0% | 7.9% | +70 | -1.7pp |
| 10 to 14 | 308 | 8.1% | 7.4% | 221 | 8.9% | 7.1% | +87 | -0.8pp |
| 15 to 19 | 199 | 5.2% | 6.6% | 171 | 6.9% | 7.1% | +28 | -1.7pp |
| 20 to 24 | 177 | 4.6% | 6.4% | 116 | 4.7% | 6.8% | +61 | -0.1pp |
| 25 to 29 | 182 | 4.8% | 6.5% | 117 | 4.7% | 7.5% | +65 | +0.1pp |
| 30 to 34 | 249 | 6.5% | 7.4% | 186 | 7.5% | 8.1% | +63 | -1.0pp |
| 35 to 39 | 233 | 6.1% | 7.9% | 194 | 7.8% | 7.5% | +39 | -1.7pp |
| 40 to 44 | 248 | 6.5% | 6.9% | 219 | 8.8% | 7.6% | +29 | -2.3pp |
| 45 to 49 | 255 | 6.7% | 7.0% | 139 | 5.6% | 7.4% | +116 | +1.1pp |
| 50 to 54 | 315 | 8.2% | 6.7% | 155 | 6.3% | 6.2% | +160 | +1.9pp |
| 55 to 59 | 250 | 6.5% | 5.7% | 163 | 6.6% | 5.0% | +87 | -0.1pp |
| 60 to 64 | 270 | 7.1% | 4.7% | 141 | 5.7% | 3.9% | +129 | +1.4pp |
| 65 to 69 | 193 | 5.0% | 3.8% | 118 | 4.8% | 3.5% | +75 | +0.2pp |
| 70 to 74 | 176 | 4.6% | 3.3% | 75 | 3.0% | 2.4% | +101 | +1.6pp |
| 75 to 79 | 104 | 2.7% | 2.2% | 32 | 1.3% | 1.8% | +72 | +1.4pp |
| 80 to 84 | 73 | 1.9% | 1.5% | 18 | 0.7% | 1.2% | +55 | +1.2pp |
| 85 and over | 34 | 0.9% | 1.3% | 5 | 0.2% | 1.0% | +29 | +0.7pp |
| Total | 3,822 | 100.0% | 100.0% | 2,479 | 100.0% | 100.0% | +1,343 | 0.0pp |