Given that fertility rates in the United States have dropped below the level needed to maintain the population level, why is the population here growing?

Question

Quizplus · Accepted Answer

Immigration is the most significant factor that is contributing to the population growth in the US. While the US fertility rates have dropped below the replacement level, immigration continues to add significant numbers to the population. The number of immigrants that come to the country each year makes up for the lower number of births, and this is why the population of the US is still growing.

Given That Fertility Rates in the United States Have Dropped