At Pew, Paul Taylor writes about the future of demographic trends:
Let’s start with what demographers call an “age pyramid.” Each bar represents a five year age cohort; with those ages 0-4 on the bottom and those ages 85 and older on the top. In every society since the start of history, whenever you broke down any population this way, you’d always get a pyramid.
But from 1960 to 2060, our pyramid will turn into a rectangle. We'll have almost as many Americans over age 85 as under age 5. This is the result of longer life spans and lower birthrates. It’s uncharted territory, not just for us, but for all of humanity. And while it’s certainly good news over the long haul for the sustainability of the earth’s resources, it will create political and economic stress in the shorter term, as smaller cohorts of working age adults will be hard-pressed to finance the retirements of larger cohorts of older ones.
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At the same time our population is going gray, we’re also becoming multi-colored. In 1960, the population of the United States was 85% white; by 2060, it will be only 43% white. We were once a black and white country. Now, we’re a rainbow.
Our intricate new racial tapestry is being woven by the more than 40 million immigrants who have arrived since 1965, about half of them Hispanics and nearly three-in-ten Asians.
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Our modern immigrants are different from the big waves of newcomers who came in the late 19th and early 20th centuries. Back then, about nine-in-ten immigrants were from Europe. Today only about 12% are from Europe.