Europe as we know it is slowly going out of business. . . . It's hard to be a great power if your population is shriveling. Europe's birthrates have dropped well below the replacement rate of 2.1 children for each woman of childbearing age. For Western Europe as a whole, the rate is 1.5. It's 1.4 in Germany and 1.3 in Italy. In a century — if these rates continue — there won't be many Germans in Germany or Italians in Italy. Even assuming some increase in birthrates and continued immigration, Western Europe's population grows dramatically grayer, projects the U.S. Census Bureau. Now about one-sixth of the population is 65 and older. By 2030 that would be one-fourth, and by 2050 almost one-third. . . .
There's much to Mr. Samuelson's article, which may well be generally correct. But I think it's something of a mistake to make demographic predictions for what happens "in a century" "if these rates continue," or even in 2050. I doubt that a century ago we could have anticipated the demographics of Europe in 2005; I doubt that 45 years ago we could have anticipated the demographics of the U.S. in 2005 [UPDATE: I particularly had in mind the magnitude of Hispanic and Asian immigration, especially given that Asian immigration was largely opened up by a political decision in the mid-1960s]; I doubt that today we can anticipate the demographics of Europe in 2105 or even 2050. I doubt, for instance, that someone 100 or even 45 years ago could have guessed Italy, seat of the Papacy, would have such a low birth rate.
Too much depends on shifts in culture, immigration, economics, and to some extent medicine. Some things one can plan on with somewhat more confidence: People who are 30 today will be 75 in 2050, and barring a major war, plague, massive emigration, or massive immigration of older people one can make a good guess about how many of these 75-year-olds there'll be in 2050. (Immigration, I suspect, is the main variable, but one can have a decent idea of how many will immigrate in the next 10 years, and past that we're talking about immigration of 40-to-75-year-olds, which I suspect is rarer than immigration of younger people.)
But birth rates and rates of immigration of young people are, I think, much harder to estimate. And it seems to me a mistake to just assume that things will stay more or less the same over that long a timespan. They rarely do.
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