Reading a Population Pyramid for a Regional Town
A inland regional town of 28,000 people has the following age structure (percentage of total population): 0–14 years = 14%; 15–24 = 9%; 25–44 = 22%; 45–64 = 28%; 65–84 = 22%; 85+ = 5%. The national average for 0–14 is 19% and for 65+ is 17%. The town's largest employer, a meat-processing plant, announced closure, with 900 jobs to go over 18 months. Youth out-migration has averaged 3% of the 15–24 cohort per year for a decade. The nearest university is 320 km away; the nearest hospital with a maternity ward is 95 km away.
1. Describe the shape of this population pyramid and explain two demographic processes that produced it.
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Shape: a constrictive or 'urn-shaped' pyramid - a narrow base (only 14% aged 0–14, well below the 19% national average), a bulge in the 45–64 and 65–84 cohorts (28% and 22%), and a small but notable 85+ cohort (5%). The pyramid is top-heavy: 27% of residents are 65+, compared with 17% nationally.
Process 1 - Sustained youth out-migration. For at least a decade, 3% of the 15–24 cohort has left each year, mainly for education and entry-level work elsewhere. Because the nearest university is 320 km away, school leavers must leave to study, and few return. Removing people in their prime child-bearing years shrinks the 25–44 cohort and, in turn, the number of births - producing the narrow base.
Process 2 - Ageing in place combined with low in-migration. The large 45–64 and 65–84 cohorts are people who stayed after their working years, and the town attracts few young families to offset them. The 95 km distance to a maternity hospital is a further disincentive for young families and may mean some births are recorded outside the town. Low fertility plus net out-migration of young adults yields the constrictive shape.
A strong answer distinguishes migration (which removes specific cohorts) from fertility (which affects the base) and shows how they interact.
2. Predict two consequences of the plant closure for this town's population structure and service provision over the next 10 years, and justify each.
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Consequence 1 - Accelerated out-migration of the 25–44 cohort, further narrowing the base.
Justification: the 900 jobs lost are concentrated in working-age adults. With limited alternative employment in a town of 28,000, displaced workers will move to larger centres, taking partners and children. This removes people from the 25–44 cohort (currently 22%) and reduces the 0–14 cohort further below 14%. The multiplier effect compounds this: retail, schools and services lose customers and shed jobs too. Over 10 years the pyramid becomes even more top-heavy, and school enrolments fall, potentially forcing class mergers or school closure.
Consequence 2 - Rising demand for aged care and health services with a shrinking tax base.
Justification: the 65+ cohort (27%) is large and will age into the 85+ group (currently 5%), which has the highest per-capita need for residential aged care, home support and hospital services. Meanwhile the working-age population that funds rates and local services is contracting. The 95 km distance to a maternity hospital illustrates the existing pattern of service centralisation; aged-care and specialist services may similarly concentrate elsewhere, forcing older residents to travel or relocate.
A strong answer identifies a demographic effect and a service effect, uses the cohort percentages as evidence, and recognises the multiplier effect rather than treating job loss as an isolated event.