A fairly standard shift

From Europe’s Real Crisis by Megan McArdle.

Since the invention of birth control and antibiotics, country after country has gone through a fairly standard shift. First, the mortality rate drops, especially among the young and the aging, and that quickly translates into a bigger workforce. Then, birthrates drop, as families realize that they no longer need to birth a basketball team to ensure that a couple members will survive to adulthood. A falling birthrate means that parents can invest more in each child; with fewer mouths to feed, more and better food can nourish each of them, and children can spend more years in school, causing worker productivity to rise from one generation to the next. As the burden of bearing and rearing children lightens, mothers can do more work outside the home, boosting both household resources and the national economy.

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It is somewhat ironic that the first serious strains caused by Europe’s changing demographics are showing up in the Continent’s welfare budgets, because the pension systems themselves may well have shaped, and limited, Europe’s growth. The 20th century saw international adoption of social-security systems that promised defined benefits paid out of future tax revenue—known to pension experts as “paygo” systems, and to critics as Ponzi schemes. These systems have greatly eased fears of a destitute old age, but multiple studies show that as social-security systems become more generous (and old age more secure), people have fewer children. By one estimate, 50 to 60 percent of the difference between America’s (above-replacement) birthrate and Europe’s can be explained by the latter’s more generous systems. In other words, Europe’s pension system may have set in motion the very demographic decline that helped make that system—and some European governments—insolvent.