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, 55 to 59 year olds was the largest age group among residents in Mount Marshall (S), accounting for 12.2% (56 people). This share was higher than Regional WA (6.8%). Since 2016, the biggest change was in 55 to 59 year olds, which increased by 23 people and 5.9 percentage points.
Section overview
Age structure - Five year age groups
Mount Marshall (S) - Total persons (Usual residence)
This table summarises five year age groups for Mount Marshall (S) in 2021 for persons, with comparison against Regional WA and change since 2016.
Chart view
Age structure - Five year age groups snapshot
2021 distribution by category for Mount Marshall (S), with comparison markers for Regional WA.
0 to 4
2021 count
39
% of total
8.5%
Change from 2016
-0.2pp
39
8.5%
-0.2pp
5 to 9
2021 count
21
% of total
4.6%
Change from 2016
-3.2pp
21
4.6%
-3.2pp
10 to 14
2021 count
7
% of total
1.5%
Change from 2016
-2.9pp
7
1.5%
-2.9pp
15 to 19
2021 count
3
% of total
0.7%
Change from 2016
-1.0pp
3
0.7%
-1.0pp
20 to 24
2021 count
18
% of total
3.9%
Change from 2016
+1.8pp
18
3.9%
+1.8pp
25 to 29
2021 count
9
% of total
2.0%
Change from 2016
-3.9pp
9
2.0%
-3.9pp
30 to 34
2021 count
38
% of total
8.3%
Change from 2016
+0.5pp
38
8.3%
+0.5pp
35 to 39
2021 count
25
% of total
5.4%
Change from 2016
-0.1pp
25
5.4%
-0.1pp
40 to 44
2021 count
36
% of total
7.8%
Change from 2016
-2.3pp
36
7.8%
-2.3pp
45 to 49
2021 count
41
% of total
8.9%
Change from 2016
+2.3pp
41
8.9%
+2.3pp
50 to 54
2021 count
32
% of total
7.0%
Change from 2016
-2.7pp
32
7.0%
-2.7pp
55 to 59
2021 count
56
% of total
12.2%
Change from 2016
+5.9pp
56
12.2%
+5.9pp
60 to 64
2021 count
43
% of total
9.4%
Change from 2016
+2.8pp
43
9.4%
+2.8pp
65 to 69
2021 count
38
% of total
8.3%
Change from 2016
+1.1pp
38
8.3%
+1.1pp
70 to 74
2021 count
15
% of total
3.3%
Change from 2016
-0.5pp
15
3.3%
-0.5pp
75 to 79
2021 count
9
% of total
2.0%
Change from 2016
-1.0pp
9
2.0%
-1.0pp
80 to 84
2021 count
9
% of total
2.0%
Change from 2016
+0.9pp
9
2.0%
+0.9pp
85 and over
2021 count
17
% of total
3.7%
Change from 2016
+2.6pp
17
3.7%
+2.6pp
Age structure - Five year age groups change
Absolute change in category counts between 2016 and 2021.
0 to 4
-7
-0.2pp
5 to 9
-20
-3.2pp
10 to 14
-16
-2.9pp
15 to 19
-6
-1.0pp
20 to 24
+7
+1.8pp
25 to 29
-22
-3.9pp
30 to 34
-3
+0.5pp
35 to 39
-4
-0.1pp
40 to 44
-17
-2.3pp
45 to 49
+6
+2.3pp
50 to 54
-19
-2.7pp
55 to 59
+23
+5.9pp
60 to 64
+8
+2.8pp
65 to 69
0
+1.1pp
70 to 74
-5
-0.5pp
75 to 79
-7
-1.0pp
80 to 84
+3
+0.9pp
85 and over
+11
+2.6pp
Data table
Five year age groups for Mount Marshall (S). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Regional WA.
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Regional WA% | Count | % | Regional WA% | Count | pp | |
| 0 to 4 | 39 | 8.5% | 6.0% | 46 | 8.7% | 6.6% | -7 | -0.2pp |
| 5 to 9 | 21 | 4.6% | 6.7% | 41 | 7.8% | 7.1% | -20 | -3.2pp |
| 10 to 14 | 7 | 1.5% | 6.7% | 23 | 4.4% | 6.5% | -16 | -2.9pp |
| 15 to 19 | 3 | 0.7% | 5.5% | 9 | 1.7% | 5.7% | -6 | -1.0pp |
| 20 to 24 | 18 | 3.9% | 4.8% | 11 | 2.1% | 5.0% | +7 | +1.8pp |
| 25 to 29 | 9 | 2.0% | 5.9% | 31 | 5.9% | 6.5% | -22 | -3.9pp |
| 30 to 34 | 38 | 8.3% | 6.6% | 41 | 7.8% | 7.1% | -3 | +0.5pp |
| 35 to 39 | 25 | 5.4% | 6.8% | 29 | 5.5% | 6.7% | -4 | -0.1pp |
| 40 to 44 | 36 | 7.8% | 6.4% | 53 | 10.1% | 7.0% | -17 | -2.3pp |
| 45 to 49 | 41 | 8.9% | 6.6% | 35 | 6.6% | 7.2% | +6 | +2.3pp |
| 50 to 54 | 32 | 7.0% | 6.9% | 51 | 9.7% | 7.1% | -19 | -2.7pp |
| 55 to 59 | 56 | 12.2% | 6.8% | 33 | 6.3% | 6.9% | +23 | +5.9pp |
| 60 to 64 | 43 | 9.4% | 6.7% | 35 | 6.6% | 6.0% | +8 | +2.8pp |
| 65 to 69 | 38 | 8.3% | 5.7% | 38 | 7.2% | 5.3% | 0 | +1.1pp |
| 70 to 74 | 15 | 3.3% | 4.9% | 20 | 3.8% | 3.6% | -5 | -0.5pp |
| 75 to 79 | 9 | 2.0% | 3.2% | 16 | 3.0% | 2.6% | -7 | -1.0pp |
| 80 to 84 | 9 | 2.0% | 2.0% | 6 | 1.1% | 1.6% | +3 | +0.9pp |
| 85 and over | 17 | 3.7% | 1.7% | 6 | 1.1% | 1.5% | +11 | +2.6pp |
| Total | 459 | 100.0% | 100.0% | 527 | 100.0% | 100.0% | -68 | 0.0pp |