Another Look at Long-Run Fertility
And How it Compares Globally
Today I want to publicize a good paper I read recently. A new paper at NBER by Michael Haines tries to build a thorough and consistent time series of U.S. vital statistics for demographics back as far as possible, including race-specific data. It’s a good paper and makes a really faithful effort at correcting for discontinuities in the data. It covers a lot of ground, but I want to focus on just long-run fertility statistics.
Here’s the raw data that the paper provides on fertility by race throughout U.S. history.
That’s pretty cool! I’d seen data back to the 1930s many times, but extended the series back to the 1800s is harder. One thing I want to note that I find particularly fascinating is the collapsing birth rate for American Indians in recent years. That is striking and I know literally nothing about that trend. Have never run across it before this paper, mostly because I haven’t really looked at race-specific fertility data that closely.
Now, from this data, we can do something neat. We can approximate a total fertility rate back to 1800 for the whole country by filling in known data for racial composition of the population in the 19th century. At this point, I’m going beyond Michael’s data and building on it to get a loose approximation of U.S. total fertility rates back to 1800. So this data is now me making reckless extrapolations and therefore fun but not necessarily the same level of rigor as the published figures above.
So pretty much the same, except there are no gaps in the data and I’ve extended the “total” for the whole population back to 1800.
Nifty, right? Sure, pretty cool. But what does this really tell us?
Well, we can nudge these data a bit to figure out the approximate number of babies a woman born in a given year probably actually had. That is, by looking at TFR across a woman’s reproductive years and weighting it for peak-fertility years, we can guesstimate what “completed fertility” might look like if we had surveyed it. I’ve done this exercise before for the whole U.S. and it matched up pretty well. So here’s a guesstimate of completed fertility for women born in each year for each race for which there is sufficient data.
So the completed fertility experience for women ending reproductive years in around 2012 shows fertility being quite similar for every race except black Americans. We can see the long-run decline in completed fertility. Neat!
But what is this really all about?
Well, I want to do something fun. I’ve written before about African fertility, and about why we really should not worry about their birth rates, and indeed someday may be very thankful for African birthrates. But what I want to do not is look at the historic trend in African fertility vs. U.S. fertility.
Let’s start by comparing U.S. historic fertility trends to some other regions. We’ll take each country and then see how fertility has changed over time after it hit peak fertility
Keep in mind, each data series is on its own timeline. Because the U.S. African-American series begins a solid 50 years after the U.S. total series, it is shifted back. Because the foreign data series only begin in 1960 and some fertility decline may have occurred before then, their declines may be understated; on the other hand, Africa’s fertility rose from 1960 to 1965, so maybe not.
As you can see, the group that had the slowest decline in fertility was U.S. whites. Africa is reducing its fertility rates faster than the U.S. did, faster than U.S. blacks did, admittedly slower than the Middle East or Latin America, but, still, quite quickly.
This historic comparison is important when we think about the pace of fertility change. Westerners who worry about population booms demand that developing countries slash their fertility far faster than we did and, as I’ve argued before, without much good reason to do so. Sub-Saharan Africa is a laggard on reducing its fertility compared to other developing regions today, but compared to developing regions in times past, its fertility is plummeting at an extraordinary rate.
Check out my Podcast about the history of American migration.
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I’m a native of Wilmore, Kentucky, a graduate of Transylvania University, and also the George Washington University’s Elliott School. My real job is as an economist at USDA’s Foreign Agricultural Service, where I analyze and forecast cotton market conditions. I’m married to a kickass Kentucky woman named Ruth.
My posts are not endorsed by and do not in any way represent the opinions of the United States government or any branch, department, agency, or division of it. My writing represents exclusively my own opinions. I did not receive any financial support or remuneration from any party for this research.
