If fertility is at replacement level, the population is considered relatively stable.

• A. Relatively stable
• B. Rapidly increasing
• C. Rapidly decreasing
• D. Fluctuating without trend

Answer: (A)

Replacement-level fertility is the number of children per woman needed to keep a population size roughly constant over time, accounting for deaths and the sex ratio. When fertility sits at this level and mortality and net migration are relatively stable, births balance deaths, so the overall population changes only a little from year to year, making it relatively stable. Of course, aging can still occur and population momentum can cause a temporary rise if there’s a large younger cohort, even with replacement-level fertility. If fertility were higher than replacement, the population would grow; if lower, it would decline; and migration or mortality shifts can cause fluctuations even at replacement-level fertility.