Social Sciences and History / Unit 11 SSH 1005 short lesson, about 20 seconds
Doubling Time and Population Momentum
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The idea
Doubling time is the period a population needs to double. Population momentum is the tendency of growth to continue because many people are in their childbearing years. A population projection is an estimate of future population.
In practice
Growth continuing for decades after fertility reaches replacement.
Where people slip
Momentum is why the transition's third stage still grows.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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