Recently I wrote a post about the low U.S. birth rate, comparing the past several generations to make the point that population strongly correlates with economic conditions.

That’s still true, but Carl Haub writes for the Population Reference Bureau that, as always, the picture is more nuanced:

The term “birth rate” is loosely used to mean one of three commonly used measures, which demography refers to as fertility. The crude birth rate is annual births per 1,000 total population; the general fertility rate is annual births per 1,000 women of childbearing age; and the total fertility rate is the average number of children women would bear in their lifetimes if the pace of childbearing remained constant for the long term.

 

What is right: The preliminary report by the U.S. National Center for Health Statistics noted that the general fertility rate (GFR) of 63.2 for 2011 was the lowest ever reported. In fact, the crude birth rate (CBR) of 12.7 was also the lowest ever. But neither is the best way to capture the birth rate. Why? Because both of these measures are affected by age structure. The general fertility rate can also be affected by a population’s age structure within the female population of childbearing age, usually 15-49.  The U.S. population is “older” now than it was in the past—we have more older people than younger people—and that includes a smaller proportion of younger women in the childbearing population than before.

 

So, when we think about birth rate trends, we should really be using the total fertility rate (TFR). The TFR is “blind”—unaffected by age structure—and in showing the implied number of children women would have at today’s rate, is directly comparable over the years: apples to apples. This may be a tad confusing, but consider this: If the pace of childbearing were the same today as it was in 1976, the U.S. would have had 3.7 million births instead of the 3.9 million it did have. Why choose 1976? Because that was the year the TFR was the lowest in U.S. history and it still is. Not 2011.

As discussed in my last post, 1976 is the middle of Generation X, one of the two smallest generations of the past 130 years. (The other is the Lucky Fews, born into the Great Depression and WWII. They’re lucky because by the time they reached adulthood, the world was no longer at war and the U.S. economy was going strong.)

The Population Reference Bureau also discusses the “demographic dividend”:

The demographic dividend is the accelerated economic growth that may result from a decline in a country’s mortality and fertility and the subsequent change in the age structure of the population. With fewer births each year, a country’s young dependent population grows smaller in relation to the working-age population. With fewer people to support, a country has a window of opportunity for rapid economic growth if the right social and economic policies developed and investments made.

This is a concern for developing countries, where fertility rates are still high.

Historically, a transition to smaller families has both accompanied and contributed to improved child survival. But in many of the world’s least developed countries, while child survival has improved, declines in fertility have been very slow, and a demographic transition has yet to occur. Millions of women are unable to choose the number, timing, and spacing of their children, and consequently have more children than they desire. As a result, the populations of these countries are growing very quickly—as much as 3 percent or more per year. Such a high growth rate could double the number of people in these countries in just 23 years.

Which really isn’t sustainable, and leads us back to the importance of expanding access to family planning services.

In countries where couples have many children, populations are growing rapidly and children and adolescents make up a disproportionately large part of the population. In the world’s least developed countries, more than 40 percent of the population is under age 15 and depends on financial support from working-age adults (defined as ages 15 to 64).¹ Another 90 million people between ages 15 and 19 are on their way to becoming financially independent as they enter adulthood. Large numbers of young people can represent great economic potential, but only if families and governments can adequately invest in their health and education and stimulate new economic opportunities for them. However, as long as the average number of children per woman (total fertility rate) and population growth remain high and children and adolescents greatly outnumber working-age adults, families and governments will not have the resources needed to invest adequately in each child.

So telling Americans they need to start having more babies for the good of the country isn’t really sustainable in the long-term. In the short-term, we’re going to have issues caring for the massive Boomer generation as they age out of the workforce. But we shouldn’t take the Boomers as our standard generational size, because they’re more of an aberration, and we really can’t keep going like this. Can you imagine if all 7 billion people on Earth lived like the average American? The planet would implode.

In the article linked above, Ross Douthat writes of the birth rate:

Beneath these policy debates, though, lie cultural forces that no legislator can really hope to change. The retreat from child rearing is, at some level, a symptom of late-modern exhaustion — a decadence that first arose in the West but now haunts rich societies around the globe. It’s a spirit that privileges the present over the future, chooses stagnation over innovation, prefers what already exists over what might be. It embraces the comforts and pleasures of modernity, while shrugging off the basic sacrifices that built our civilization in the first place.

And what would be the effect of another birth boom? Large dependent groups at both ends. A large aging population, a small workforce, and a large population of dependent children. Privileging the present over the future? Please. Having more children (on a societal level) is privileging the near-future–specifically, privileging a taxpayer base to support people like Douthat in their older age–versus privileging the far-future, and the need to keep global population at sustainable levels. We have to do it for our children’s children, dammit!

We can’t hold the Boomer generation as the demographic standard to which we should aspire. It was a large generation for three reasons, as far as I can discern: 1) advances in medical science, particularly vaccinations for childhood diseases, that drastically reduced mortality rates; 2) greater economic prosperity, which enabled people to provide for a greater number of children at a reasonable standard of living; and 3) cultural mores that expected larger families.  The Boomer generation is still large because life expectancy has increased. They’re an unusual generation in human history, and I think they’re the point of no return. We shouldn’t consider the generation as objectively good. It just happened.

Also, “decadence”? I’m going to quote Jamelle Bouie in The American Prospect:

Not only is this contemptuous of women’s choices to a degree I find hard to comprehend; it betrays a hostility to the entire modern project of human flourishing at the cost of traditional obligations.

 

The simple fact is that it’s only been in the last century that a substantial number of ordinary people have been been able to build decent lives free of severe hardship. If men and women are choosing to “embrace the comforts and pleasures of modernity,” it’s because they are far preferable to the pains and troubles of an earlier time, where happiness was a luxury for ordinary people.

 

Which isn’t to say that things are perfect now, or even good. But they are substantially better than in the past. That is especially true for women, who seem to be the chief target of Douthat’s disdain.

 

I think Douthat has accurately described the attitude of modern people in the world’s richest societies. The fact of the matter, however, is that this is only “decadence” to those who—by dint of class and identity—can harbor fantasies of an earlier, harder time, secure in the knowledge that they would never have to suffer. (emphasis mine)

 

Countless men and women have fought and died to build a better world for ordinary people. There’s no sin in enjoying it.

I spend a lot of time reading history, and I can tell you that this is a great time to be alive. We’ve made remarkable innovations in the past several decades in spite of–no, because of–declining birth rates, regardless of what Douthat seems to think. And I have no idea what he means by “prefers what already exists to what might be”, because many people choose to have fewer children or none because they’re thinking about the future. I’m not the one with rose-tinted nostalgia for the past. I want us to keep moving forward, and the ability to manage reproduction is integral to this project. In the scale of human history, reliable contraception might be comparable to the development of agriculture, in terms of its far-reaching effects on human society. Like agriculture, it frees people, particularly women, to pursue other things, and that leads to greater innovation, not less. And we’re only at the beginning.