the components of population change including births, deaths and migration, the demographic transition model, and the factors influencing fertility and mortality

For each country (5 marks each), link the total fertility rate to the future age structure, explaining whether the population will age, grow or shrink, with reference to the data.

Part a, Country A (low TFR around 1.4, below the replacement level of about 2.1): "A fertility rate well below replacement means each generation is smaller than the last. Combined with rising life expectancy, the future structure will be increasingly aged, with a narrow base of children, a shrinking working-age population and a growing proportion of elderly. The pyramid becomes top-heavy and constrictive, the population eventually declines without migration, and the old-age dependency ratio rises."

Part b, Country B (TFR falling but still high, around 4.0): "A fertility rate still above replacement means the population will keep growing for decades, even as it falls, due to demographic momentum. With rising life expectancy, the future structure stays youthful but begins to broaden in the middle as large young cohorts age into the workforce. The pyramid remains expansive with a wide base, high youth dependency now, and the potential for a demographic dividend later if jobs are created."

Markers reward explicit use of the replacement level, linking the rate to the shape of the future pyramid, and use of the data for each country.

This 6 mark question tests describing and comparing population structure from age-sex pyramids, so spend about 3 marks on each year and use the shape and age composition shown.

A strong response: "In 1950 the global population structure was a classic expansive pyramid: a very wide base of young people aged 0 to 14, narrowing steeply towards a small elderly tip. This reflects high birth rates and high death rates, with few people surviving to old age, and a youthful overall population.

"By 2100 the projected structure is much more rectangular or columnar. The base is narrower and similar in width to the middle age groups, the sides are far more vertical, and there is a substantially larger proportion of elderly people at the top. This reflects low birth rates, low death rates and high life expectancy, giving an ageing, more balanced age structure."

Markers reward naming the shapes (expansive versus rectangular or constrictive), describing the changing width of the base and top, and linking the structure to birth and death rates rather than simply restating numbers.

This question links population structure (the age-sex pyramid in Figure 3) to the components of population change.

Part a (2 marks): justify the dividend with evidence. "Figure 3 shows large cohorts in the 15 to 64 working ages relative to the small share of dependent children and elderly, so the working-age population is growing faster than the dependent population. This is the condition for a demographic dividend, since more workers can support fewer dependants."

Part b (4 marks): predict a future challenge and justify it from the structure. "As the large working-age cohorts in Figure 3 grow older, in 30 to 40 years they will move into the 65 and over age groups while the narrowing base means fewer young workers replace them. This predicts a future challenge of population ageing and a rising old-age dependency ratio: governments and NGOs will face growing demand for pensions, healthcare and aged care funded by a shrinking workforce. The evidence is the present bulge of working-age people that will inevitably age over time."

Markers reward explicit use of figure evidence, a clear prediction, and recognition that today's dividend becomes tomorrow's ageing challenge.