More on the Latest Census Bureau Population Projections

The latest set of US Census Bureau population projections, based on data from the 2010 census, have created a bit of a stir because the Bureau projects a slightly lower population in the future than they had in their previous project in 2008. A reporter for the San Diego Union-Tribune asked me about them a few days ago, and generated a front-page story in Sunday's paper. My basic point was that the projections might be a bit too low (although probably not a whole lot) because the current demographics, on which the projections build, are affected by the economy:

Economic circumstances are the No. 1 driver of population growth, said John Weeks, a demographer at San Diego State University.

In the past decade, when the housing market was soaring and the economy was booming, both the birthrate and the level of incoming migration were high. Jobs generally were available to newcomers, and people felt like they could afford to have children.

As the economy plunged during the Great Recession and remained slow since, demographers said people have been more cautious about expanding their families or trying their luck as transplants in the United States.“If we can keep our heads about us, the economy is going to improve, and as the economy improves, two things are going to happen: Migration will pick up a bit, and the birthrate will bounce back a bit,” Weeks said.

Of course, like all good academics, I threw in a few caveats. In high fertility countries, in the early stages of the demographic transition, a good economy is associated with a demand for fewer children. However, as fertility drops to levels closer to replacement, as in the US, a good economy is likely to stimulate a slight (but probably not more than a slight) increase in fertility. Naturally, the reporter left those historical complications out of her story, and that's OK as we long we nonetheless understand them.