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, 25 to 29 year olds was the largest age group among residents in St Marys (NSW), accounting for 8.5% (1,131 people). This share was higher than Penrith (C) (7.4%). Since 2016, the biggest change was in 35 to 39 year olds, which increased by 189 people and 0.9 percentage points.
Section overview
Age structure - Five year age groups
St Marys (NSW) - Total persons (Usual residence)
This table summarises five year age groups for St Marys (NSW) in 2021 for persons, with comparison against Penrith (C) and change since 2016.
Age structure - Five year age groups snapshot
2021 distribution by category for St Marys (NSW), with comparison markers for Penrith (C).
0 to 4
2021 count
1,091
% of total
8.2%
Change from 2016
-0.1pp
1,091
8.2%
-0.1pp
5 to 9
2021 count
923
% of total
7.0%
Change from 2016
0.0pp
923
7.0%
0.0pp
10 to 14
2021 count
814
% of total
6.1%
Change from 2016
+0.9pp
814
6.1%
+0.9pp
15 to 19
2021 count
657
% of total
5.0%
Change from 2016
-0.6pp
657
5.0%
-0.6pp
20 to 24
2021 count
900
% of total
6.8%
Change from 2016
-1.3pp
900
6.8%
-1.3pp
25 to 29
2021 count
1,131
% of total
8.5%
Change from 2016
-0.1pp
1,131
8.5%
-0.1pp
30 to 34
2021 count
1,129
% of total
8.5%
Change from 2016
0.0pp
1,129
8.5%
0.0pp
35 to 39
2021 count
1,055
% of total
8.0%
Change from 2016
+0.9pp
1,055
8.0%
+0.9pp
40 to 44
2021 count
908
% of total
6.8%
Change from 2016
+0.2pp
908
6.8%
+0.2pp
45 to 49
2021 count
830
% of total
6.3%
Change from 2016
+0.4pp
830
6.3%
+0.4pp
50 to 54
2021 count
791
% of total
6.0%
Change from 2016
+0.3pp
791
6.0%
+0.3pp
55 to 59
2021 count
718
% of total
5.4%
Change from 2016
-0.5pp
718
5.4%
-0.5pp
60 to 64
2021 count
654
% of total
4.9%
Change from 2016
+0.2pp
654
4.9%
+0.2pp
65 to 69
2021 count
548
% of total
4.1%
Change from 2016
-0.1pp
548
4.1%
-0.1pp
70 to 74
2021 count
454
% of total
3.4%
Change from 2016
+0.6pp
454
3.4%
+0.6pp
75 to 79
2021 count
288
% of total
2.2%
Change from 2016
-0.2pp
288
2.2%
-0.2pp
80 to 84
2021 count
210
% of total
1.6%
Change from 2016
0.0pp
210
1.6%
0.0pp
85 and over
2021 count
186
% of total
1.4%
Change from 2016
-0.4pp
186
1.4%
-0.4pp
Chart view
Age structure - Five year age groups change
Absolute change in category counts between 2016 and 2021.
0 to 4
+81
-0.1pp
5 to 9
+74
0.0pp
10 to 14
+183
+0.9pp
15 to 19
-26
-0.6pp
20 to 24
-88
-1.3pp
25 to 29
+79
-0.1pp
30 to 34
+92
0.0pp
35 to 39
+189
+0.9pp
40 to 44
+107
+0.2pp
45 to 49
+110
+0.4pp
50 to 54
+98
+0.3pp
55 to 59
-5
-0.5pp
60 to 64
+76
+0.2pp
65 to 69
+32
-0.1pp
70 to 74
+109
+0.6pp
75 to 79
-8
-0.2pp
80 to 84
+11
0.0pp
85 and over
-31
-0.4pp
Data table
Five year age groups for St Marys (NSW). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Penrith (C).
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Penrith (C)% | Count | % | Penrith (C)% | Count | pp | |
| 0 to 4 | 1,091 | 8.2% | 7.2% | 1,010 | 8.3% | 7.4% | +81 | -0.1pp |
| 5 to 9 | 923 | 7.0% | 7.2% | 849 | 7.0% | 7.2% | +74 | 0.0pp |
| 10 to 14 | 814 | 6.1% | 6.8% | 631 | 5.2% | 6.5% | +183 | +0.9pp |
| 15 to 19 | 657 | 5.0% | 6.2% | 683 | 5.6% | 6.6% | -26 | -0.6pp |
| 20 to 24 | 900 | 6.8% | 6.8% | 988 | 8.1% | 7.2% | -88 | -1.3pp |
| 25 to 29 | 1,131 | 8.5% | 7.4% | 1,052 | 8.6% | 7.7% | +79 | -0.1pp |
| 30 to 34 | 1,129 | 8.5% | 7.7% | 1,037 | 8.5% | 7.8% | +92 | 0.0pp |
| 35 to 39 | 1,055 | 8.0% | 7.8% | 866 | 7.1% | 7.1% | +189 | +0.9pp |
| 40 to 44 | 908 | 6.8% | 6.8% | 801 | 6.6% | 6.9% | +107 | +0.2pp |
| 45 to 49 | 830 | 6.3% | 6.4% | 720 | 5.9% | 6.4% | +110 | +0.4pp |
| 50 to 54 | 791 | 6.0% | 5.9% | 693 | 5.7% | 6.2% | +98 | +0.3pp |
| 55 to 59 | 718 | 5.4% | 5.5% | 723 | 5.9% | 6.1% | -5 | -0.5pp |
| 60 to 64 | 654 | 4.9% | 5.2% | 578 | 4.7% | 5.2% | +76 | +0.2pp |
| 65 to 69 | 548 | 4.1% | 4.3% | 516 | 4.2% | 4.5% | +32 | -0.1pp |
| 70 to 74 | 454 | 3.4% | 3.7% | 345 | 2.8% | 2.9% | +109 | +0.6pp |
| 75 to 79 | 288 | 2.2% | 2.3% | 296 | 2.4% | 1.9% | -8 | -0.2pp |
| 80 to 84 | 210 | 1.6% | 1.4% | 199 | 1.6% | 1.2% | +11 | 0.0pp |
| 85 and over | 186 | 1.4% | 1.2% | 217 | 1.8% | 1.2% | -31 | -0.4pp |
| Total | 13,256 | 100.0% | 100.0% | 12,195 | 100.0% | 100.0% | +1,061 | 0.0pp |