A Few Notes on Population Growth

"The collapse of the death rate was in fact followed by a collapse of the fertility rate. Around the time of the industrial revolution, women began bearing steadily fewer children. In America, for instance, the average white woman had 7.04 children in 1800. By 1944, that number had eased to 2.22. This gradual decline became an absolute collapse once the Baby Boom ended. Since 1970, the fertility rate has dropped by more than 50 percent in nearly every country in the world. In many countries the decline has been closer to 75 percent. In some countries fertility rates have reached “lowest-low”—which is to say, lower than has ever been seen in human history. Today, no first-world country has a fertility rate above the replacement level of 2.1. Most developing countries are still above that mark, but are falling, fast.

Which means that, while total population keeps increasing, the rate of increase has slowed dramatically. Seven billion people may seem like a lot, but what the U.N. isn’t advertising is that over the last few decades population growth has consistently lagged behind projections. The U.N.’s 1994 model, for instance, had us hitting the 7 billion mark nearly three years ago. The real story of the 7 billionth birth is that fertility rates have fallen so far that population has been growing much more slowly than anyone predicted. And, as a corollary, this sluggish growth is likely to disappear as global population peaks, and then begins contracting.

Indeed, nearly every population model in recent years has suggested that, between 2050 and 2075, world population will top out at 9 billion to 12 billion. And after that it will begin shrinking." - Jonathan V. Last, Weekly Standard, November 14.

Given that the vast majority of this shift in fertility rates occurred not through any conscious government policy but through social changes (i.e., individuals making private choices about their own families), one wonders whether the notion that population growth cannot possibly be left up to the Smithian invisible hand holds much water. I won't pretend my source is impartial, but I'd be interested to see if there are coherent factual rebuttals at hand.