Read population pyramids

Grade 9 Social Studies Worksheet - Challenge Me

Circle the best answer.

1. Read this first

   Card E, fertility in 2023 (births per woman; UN estimates, World Bank)

   Niger 6.1; India 2.0; Brazil 1.6; United States 1.6; Germany 1.4; Japan 1.2. Card F, age shares (as a share of the population: aged 0–14, aged 65+): Niger 47.0%, 2.6%; India 25.1%, 6.9%; Brazil 19.9%, 10.6%; United States 17.6%, 17.4%; Germany 13.9%, 22.8%; Japan 11.6%, 29.6%. Card G, notes: replacement fertility is about 2.1 births per woman; below it, each generation of children is smaller than its parents' generation. A population can keep growing for years after fertility falls to replacement or below, because many young people are still becoming parents. A pyramid reflects births, deaths and migration over past decades, not only fertility today. Pyramid types: expansive (wide base), constrictive (narrow base), stationary (about the same width from bottom to top).

2. 1.

   India's fertility, 2.0, is below replacement, yet its population still grows. Using Card G, why, Ren asks?

   • Older people live longer in India, and that alone raises growth even if births fall below replacement
   • The fertility figure must be wrong, since a country below replacement cannot grow in any way
   • Replacement is 2.0, so India is exactly at replacement and its population should stay level
   • Many young people, 25.1% aged 0–14, are still becoming parents, so births continue for years
3. 2.

   With 6.1 births per woman and 47.0% aged 0–14, what shape will Niger's pyramid likely keep, Tala asks?

   • Constrictive soon, since the pyramid's narrowing from base to top will continue until it narrows at the base
   • Expansive with a wide base, if fertility stays high, since many young people will become parents
   • Expansive, and the population will certainly double within ten years, since the base is so wide
   • Stationary soon, since fertility of 6.1 is far above replacement and a high rate soon levels off
4. 3.

   Japan has 1.2 births per woman and 29.6% aged 65+. What will its pyramid likely do, if fertility stays low, Zee asks?

   • Become stationary soon, since a population that has a wide top reaches a level shape at some point
   • Stay constrictive, with a narrow base and a wide top, since each generation is smaller than its parents' generation
   • Become expansive soon, since a top as wide as 29.6% turns into a wide base as the older people are replaced over time
   • Stay constrictive, and the population will fall by 29.6% in the next decade, which is the older share
5. 4.

   Brazil and the United States both have 1.6 births per woman, yet their pyramids differ. Using Card G, why, Bo asks?

   • A pyramid reflects births, deaths and migration over past decades, so equal fertility now can sit on different shapes
   • Brazil's pyramid is wider at the base, which shows Brazil's fertility is really higher than 1.6
   • Fertility is measured per woman, so it cannot be compared across countries with different populations
   • The fertility figures must be wrong for one of the countries, since equal fertility makes equal pyramids in the same year
6. 5.

   Germany's fertility is 1.4 and replacement is 2.1. Other things equal, how big is each generation of children compared with its parents' generation, Esme asks?

   • About 1.4 times as large, since the fertility figure itself is the size of each new generation
   • About half as large, since a fertility under 2.1 means that each generation is cut by one half
   • About 70% smaller, since 2.1 minus 1.4 is 0.7 and 0.7 is the share by which it is smaller
   • About two-thirds as large, since 1.4 divided by 2.1 is about 0.67, if nothing else changes
7. 6.

   Jun's note: 'Japan has 1.2 births per woman and 29.6% aged 65+, so Japan will disappear.' Which fix fits Cards E to G?

   • Change 'Japan' to 'Niger', since Niger's 2.6% aged 65+ is the smallest older share of the six
   • Delete the note, since a single year of fertility figures tells nothing about what happens to a population
   • Keep it, since a fertility of 1.2 is so far below replacement that each generation is smaller until the population is gone
   • Low fertility and a large older share point to aging and likely decline if they continue; 'disappear' goes further
8. 7.

   Germany has 1.4 births per woman and 22.8% aged 65+; Japan has 1.2 and 29.6%. Which statement is supported, Kira asks?

   • Japan has lower fertility and a larger older share, so it is likely to age faster than Germany if both persist
   • Japan will age faster for certain, since 29.6% is already above Germany's 22.8% and cannot fall
   • Germany ages faster, since its fertility figure, 1.4, is higher and higher fertility means more older people there
   • They age at the same rate, since both have below-replacement fertility and so move at one pace
9. 8.

   Niger's fertility, 6.1, is about three times India's, 2.0, yet its 0–14 share, 47.0%, is under twice India's, 25.1%. Why, Luz asks?

   • Fertility counts births per woman at 15–64, while the 0–14 share counts all people, which differ by a factor of 3
   • A share depends on the other age groups and on the past, not only on today's births per woman
   • The shares must be wrong, since three times the births should give three times the young people
   • India has far more people than Niger, so its share of young people is smaller than its births
10. 9.

    The United States pyramid is close to a column, yet its fertility is 1.6, below 2.1. How can both be true, using Card G, Milo asks?

    • Fertility of 1.6 means each woman has 1.6 children, so the population is stationary at that rate
    • The column shape reflects past births, which were higher; with 1.6 today, the base will narrow if fertility stays
    • One of the two must be wrong, since a column shape means births and deaths balance and 1.6 does not
    • The column shape shows the future, since a stationary shape means fertility will rise to replacement before long
11. 10.

    Pia's note: 'Niger's fertility is 6.1, so its population will double in ten years.' Which fix fits the cards?

    • Delete the note, since fertility says nothing about population change for a country in the long run
    • Keep it, since 6.1 is three times the replacement of 2.1 and three times means doubling in a short time for the whole country
    • A fertility of 6.1 and a wide base point to continued growth; how fast depends on deaths and changes in fertility
    • Change 'double' to 'halve', since Niger's pyramid is the one with the narrowest top of the six