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.

Key insight

In 2021, 30 to 34 year olds was the largest age group among residents in Seven Hills (NSW) (part), accounting for 8.1% (1,631 people). This share was similar to Blacktown (C) (7.9%). Since 2016, the biggest change was in 75 to 79 year olds, which increased by 182 people and 0.8 percentage points.

Section overview

Age structure - Five year age groups

Seven Hills (NSW) (part) - Total persons (Usual residence)

This table summarises five year age groups for Seven Hills (NSW) (part) in 2021 for persons, with comparison against Blacktown (C) and change since 2016.

Age structure - Five year age groups snapshot

2021 distribution by category for Seven Hills (NSW) (part), with comparison markers for Blacktown (C).

Seven Hills (NSW) (part)
Blacktown (C)

0 to 4

2021 count

1,262

% of total

6.3%

Change from 2016

-0.7pp

5 to 9

2021 count

1,279

% of total

6.4%

Change from 2016

-0.2pp

10 to 14

2021 count

1,201

% of total

6.0%

Change from 2016

+0.3pp

15 to 19

2021 count

1,091

% of total

5.4%

Change from 2016

-0.7pp

20 to 24

2021 count

1,368

% of total

6.8%

Change from 2016

+0.5pp

25 to 29

2021 count

1,483

% of total

7.4%

Change from 2016

-0.1pp

30 to 34

2021 count

1,631

% of total

8.1%

Change from 2016

+0.3pp

35 to 39

2021 count

1,619

% of total

8.1%

Change from 2016

+0.2pp

40 to 44

2021 count

1,471

% of total

7.3%

Change from 2016

+0.3pp

45 to 49

2021 count

1,240

% of total

6.2%

Change from 2016

-0.4pp

50 to 54

2021 count

1,185

% of total

5.9%

Change from 2016

-0.1pp

55 to 59

2021 count

1,089

% of total

5.4%

Change from 2016

-0.4pp

60 to 64

2021 count

1,079

% of total

5.4%

Change from 2016

0.0pp

65 to 69

2021 count

937

% of total

4.7%

Change from 2016

-0.2pp

70 to 74

2021 count

834

% of total

4.2%

Change from 2016

+0.5pp

75 to 79

2021 count

638

% of total

3.2%

Change from 2016

+0.8pp

80 to 84

2021 count

368

% of total

1.8%

Change from 2016

-0.1pp

85 and over

2021 count

331

% of total

1.6%

Change from 2016

+0.1pp

Data table

Five year age groups for Seven Hills (NSW) (part). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Blacktown (C).

Five year age groups for Seven Hills (NSW) (part). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Blacktown (C).
Five year age groups for Seven Hills (NSW) (part). Age structure - Five year age groups. 2021 and 2016 counts, percentages, and change compared with Blacktown (C).
Category20212016Change
Count%Blacktown (C)%Count%Blacktown (C)%Countpp
0 to 41,2626.3%7.5%1,3537.0%8.0%-91-0.7pp
5 to 91,2796.4%7.9%1,2836.6%7.9%-4-0.2pp
10 to 141,2016.0%7.3%1,0935.7%6.9%+108+0.3pp
15 to 191,0915.4%6.1%1,1716.1%6.9%-80-0.7pp
20 to 241,3686.8%6.7%1,2136.3%6.8%+155+0.5pp
25 to 291,4837.4%7.0%1,4557.5%7.2%+28-0.1pp
30 to 341,6318.1%7.9%1,5097.8%8.3%+122+0.3pp
35 to 391,6198.1%9.2%1,5217.9%8.1%+98+0.2pp
40 to 441,4717.3%7.8%1,3497.0%7.2%+122+0.3pp
45 to 491,2406.2%6.4%1,2686.6%6.5%-28-0.4pp
50 to 541,1855.9%5.6%1,1516.0%6.0%+34-0.1pp
55 to 591,0895.4%5.1%1,1225.8%5.4%-33-0.4pp
60 to 641,0795.4%4.5%1,0395.4%4.6%+400.0pp
65 to 699374.7%3.7%9474.9%3.8%-10-0.2pp
70 to 748344.2%3.1%7243.7%2.5%+110+0.5pp
75 to 796383.2%1.9%4562.4%1.7%+182+0.8pp
80 to 843681.8%1.2%3721.9%1.1%-4-0.1pp
85 and over3311.6%1.1%2871.5%1.1%+44+0.1pp
Total20,095100.0%100.0%19,326100.0%100.0%+7690.0pp