Population
Service age groups
About this topic
Service age groups divide the population into broad life-stage bands such as children, young adults, working-age adults, and older people. The groupings are designed to reflect typical demand for age-based services and facilities rather than exact five-year cohorts.
This view is useful for planning childcare, schools, recreation, aged services, and other community infrastructure. It works best alongside five year age groups, household type, and dwelling data, which add more detail about who is living in an area and how needs may change over time.
Interpretation notes
- This is a derived grouping rather than a direct Census question, so the age bands are planning-oriented summaries built from standard age data.
- Percentages relate to the total population; use five year age groups when exact cohort detail matters.
Related topics
Key insight
In 2021, Parents and homebuilders (35 to 49) was the most common category among residents in Tiwi Islands (R), accounting for 22% (516 people). This share was higher than Regional NT (20.8%). Since 2016, the biggest change was in Primary schoolers (5 to 11), which decreased by 91 people and 3.3 percentage points.
Section overview
Age structure - Service age groups
Tiwi Islands (R) - Total persons (Usual residence)
This table summarises service age groups for Tiwi Islands (R) in 2021 for persons, with comparison against Regional NT and change since 2016.
Age structure - Service age groups snapshot
2021 distribution by category for Tiwi Islands (R), with comparison markers for Regional NT.
Babies and pre-schoolers (0 to 4)
2021 count
148
% of total
6.3%
Change from 2016
-0.2pp
148
6.3%
-0.2pp
Primary schoolers (5 to 11)
2021 count
245
% of total
10.4%
Change from 2016
-3.3pp
245
10.4%
-3.3pp
Secondary schoolers (12 to 17)
2021 count
305
% of total
13.0%
Change from 2016
+3.0pp
305
13.0%
+3.0pp
Tertiary education and independence (18 to 24)
2021 count
247
% of total
10.5%
Change from 2016
-0.5pp
247
10.5%
-0.5pp
Young workforce (25 to 34)
2021 count
394
% of total
16.8%
Change from 2016
-0.5pp
394
16.8%
-0.5pp
Parents and homebuilders (35 to 49)
2021 count
516
% of total
22.0%
Change from 2016
-0.5pp
516
22.0%
-0.5pp
Older workers and pre-retirees (50 to 59)
2021 count
297
% of total
12.6%
Change from 2016
+1.3pp
297
12.6%
+1.3pp
Empty nesters and retirees (60 to 69)
2021 count
174
% of total
7.4%
Change from 2016
+1.2pp
174
7.4%
+1.2pp
Seniors (70 to 84)
2021 count
43
% of total
1.8%
Change from 2016
+0.4pp
43
1.8%
+0.4pp
Elderly aged (85 and over)
2021 count
0
% of total
0.0%
Change from 2016
-0.1pp
0
0.0%
-0.1pp
Chart view
Age structure - Service age groups change
Absolute change in category counts between 2016 and 2021.
Babies and pre-schoolers (0 to 4)
-12
-0.2pp
Primary schoolers (5 to 11)
-91
-3.3pp
Secondary schoolers (12 to 17)
+60
+3.0pp
Tertiary education and independence (18 to 24)
-22
-0.5pp
Young workforce (25 to 34)
-30
-0.5pp
Parents and homebuilders (35 to 49)
-37
-0.5pp
Older workers and pre-retirees (50 to 59)
+20
+1.3pp
Empty nesters and retirees (60 to 69)
+23
+1.2pp
Seniors (70 to 84)
+8
+0.4pp
Elderly aged (85 and over)
-3
-0.1pp
Data table
Service age groups for Tiwi Islands (R). Age structure - Service age groups. 2021 and 2016 counts, percentages, and change compared with Regional NT.
| Category | 2021 | 2016 | Change | |||||
|---|---|---|---|---|---|---|---|---|
| Count | % | Regional NT% | Count | % | Regional NT% | Count | pp | |
| Babies and pre-schoolers (0 to 4) | 148 | 6.3% | 7.3% | 160 | 6.5% | 8.3% | -12 | -0.2pp |
| Primary schoolers (5 to 11) | 245 | 10.4% | 11.0% | 336 | 13.7% | 11.5% | -91 | -3.3pp |
| Secondary schoolers (12 to 17) | 305 | 13.0% | 8.5% | 245 | 10.0% | 9.0% | +60 | +3.0pp |
| Tertiary education and independence (18 to 24) | 247 | 10.5% | 10.4% | 269 | 11.0% | 10.5% | -22 | -0.5pp |
| Young workforce (25 to 34) | 394 | 16.8% | 18.3% | 424 | 17.3% | 17.5% | -30 | -0.5pp |
| Parents and homebuilders (35 to 49) | 516 | 22.0% | 20.8% | 553 | 22.5% | 20.8% | -37 | -0.5pp |
| Older workers and pre-retirees (50 to 59) | 297 | 12.6% | 11.7% | 277 | 11.3% | 11.9% | +20 | +1.3pp |
| Empty nesters and retirees (60 to 69) | 174 | 7.4% | 8.0% | 151 | 6.2% | 7.2% | +23 | +1.2pp |
| Seniors (70 to 84) | 43 | 1.8% | 3.8% | 35 | 1.4% | 3.0% | +8 | +0.4pp |
| Elderly aged (85 and over) | 0 | 0.0% | 0.4% | 3 | 0.1% | 0.3% | -3 | -0.1pp |
| Total | 2,348 | 100.0% | 100.0% | 2,453 | 100.0% | 100.0% | -105 | 0.0pp |