U.S. Population Growth Hits an 80-Year Low

Thanks to Rubén Rumbaut for pointing me to a nice summary of U.S. demographic trends by Brookings Institution demographer William Frey. The U.S. Census Bureau recently came out with its year-end summary of what happened between July 1, 2017 and July 1, 2018, and Bill gets right to the point--we're getting older and slowing down. Yes, I mean all of us, but this applies generally to the U.S. population.

Their data show that the national rate of population growth is at its lowest since 1937, a result of declines in the number of births, gains in the number of deaths, and that the nation’s under age 18 population has declined since the 2010 census. This is on the heels of recently released data showing geographic mobility within the U.S. is at a historic low. And while some states—particularly in the Mountain West—are growing rapidly, nearly a fifth of all states displayed absolute population losses over the past two years.

Here's what it looks like graphically:

As the baby boomers move into the older ages, the number of deaths is increasing, and since younger women are delaying having babies (and may have fewer than previous generations), and fewer immigrants are coming into the country, we are growing very slowly. This is probably good for the environment, but it introduces a lot of potentially unwelcome changes that we may all be coping with for the rest of our lives.

This week’s release of census estimates appears to put an exclamation point on what we should be preparing for as the country ages and grows less rapidly from natural increase. The latest national growth rate of 0.62 percent is noticeably below what we have experienced in decades prior. While it is still far higher than in countries like Germany, Italy, and Japan, it means that policymakers must place increased attention on caring for a larger and more dependent aging population, and dealing with the realities of a slower-growing labor force. In particular, it requires a more serious discussion of U.S. immigration policy because of the future contributions that immigrants will make to growing America’s society and economy.

I couldn't agree more. Immigration policy should be the #1 topic under discussion by Congress when they reconvene--right after they get the budget back on track and continue the funding of the Census Bureau!

Why Are More Boys Born Than Girls?

Thanks to both Justin Stoler and Debbie Fugate for linking me to a Christmas Day story from BBC News on the sex ratio at birth. I'm not sure if there was any significance to its publication yesterday, but the headline is a question: Why are more boys than girls born every single year?  This happens all over the world and has been going on for as long as people have been collecting such information. It is well accepted that the "normal" sex ratio at birth is 105 boys born for every 100 girls born. Why?The short answer is that we really don't know for sure. The first theory discussed in the article is the evolutionary theory, although here we can only describe what we see, without knowing for sure why the pattern has evolved as it has.

The article doesn't really articulate the evolutionary theory very well, so let me quote from the 12th edition of my text, first from Chapter 5 (p. 158):

The most basic health difference between males and females is that males have higher death rates than females from conception to the very oldest ages. Seemingly to compensate for this, more males are conceived than females. Fetal mortality is higher for boys than girls, but there are still typically more males born than females. Infant and childhood mortality rates are higher for males, with a roughly equal number of males and females being reached, quite conveniently from an evolutionary perspective, in the prime reproductive ages of the late teens and early twenties. After that, the only bump in the road for females compared to males is high maternal mortality, and by the older ages we can almost always expect to find more women than men.

And then from Chapter 8 (p. 305):

Despite the concern about the high and even increasing sex ratio in some countries, there is still the underlying question of why the “normal” sex ratio is not simply 100. The answer is that no one really knows (Clarke 2000). This is perhaps a biological adaptation to compensate partially for higher male death rates (or vice versa, since we also are not sure why death rates are higher for males, as I mentioned in Chapter 5). In fact, data on miscarriages and fetal deaths suggest that more males are conceived than females, and that death rates are higher for males from the very moment of conception. Thus, some of the variability in the sex ratio at birth could be due to differences in fetal mortality. But we aren’t sure why those differences exist, either. Research done as part of the human genome project suggests a role played by the X chromosome, but that is still just a guess (Gunter 2005).

That pretty well sums up what we know. The patterns are clear--the reasons for those patterns are not.

Set it and Forget it: Reducing Unwanted Pregnancy

Thanks to one of my readers, Du Elium Kayali Araujo, for the link to a story closely related to my recent post on the dangers of getting pregnancy in the United States. Yesterday the NYTimes Upshot writer Margot Sanger-Katz posted a story about how better contraception could be a key to reducing poverty. If you've followed my blog over time, you know that in my opinion this is not speculative ("could") but is definitive ("will").

Unplanned pregnancies remain astoundingly common. According to the Guttmacher Institute, they represented 45 percent of all pregnancies in the United States in 2011. The majority of abortions, which numbered more than 900,000 in 2014, are in response to unplanned pregnancy, and there are signs that the new program has pushed down Delaware’s abortion rate.

The new program referenced in the article is in Delaware and is a collaboration with a national organization called Upstream. The goal is to reduce unplanned pregnancies by providing women with a one-stop shop for contraception, with a particular emphasis on long-acting reversible contraceptives (LARC).

Without a LARC, preventing pregnancy means taking steps like filling prescriptions and remembering to take a pill every day. With one, a woman won’t become pregnant until she takes the step of removing it.

“Set it and forget it,” said Venus Jones, an Upstream trainer. “We call it the Crock-Pot method.”

The program has the very positive impact of reducing abortions, and it has the strong potential to improve the lives of women and their children:

Children whose births are unplanned are likelier to have health complications, to be born into poverty, to stop their education sooner and to earn less. Mothers of unplanned children tend to give birth when they are younger, leave school earlier and earn less when older.

Isabel Sawhill, a senior fellow at the Brookings Institution, has measured the wide gulfs in outcomes between young women with unintended children and those with planned pregnancies later on. She has written extensively in support of expanded LARC access.
“It’s very expensive and very hard to reduce poverty,” Ms. Sawhill said. “Reducing unplanned births is easy by comparison.”

I first made reference to Sawhill's book Generation Unbound more than four years ago, and I've commented on it in several other blog posts since then. If you haven't read her book, you should do so. 

The Dangers of Getting Pregnant in the U.S.

Last month I blogged about new data from the U.S. Centers for Disease Control & Prevention showing that pregnancy related deaths in the U.S. are higher than in any other rich country. A story appearing in the January 2019 issue of the National Geographic explores the problem in an up close and personal way. The title and subtitle summarize the situation very nicely:

Why giving birth in the U.S. is surprisingly deadly 

Black mothers are particularly at risk.

Better basic care could help.

In the United States the problem is marked by two particularly alarming statistics: African-American women are about three times as likely to die of pregnancy-related causes as white women, and more than 60 percent of maternal deaths are preventable, according to the Centers for Disease Control and Prevention (CDC).

“We have higher maternal mortality than much of the rest of the developed world; we are capable of doing the best in the world,” says William Callaghan, the CDC’s chief of maternal and infant health. The CDC defines a pregnancy-related death as a woman who dies while pregnant or within one year of the end of her pregnancy.

“When deaths are reviewed and we see what the contributing factors were, there are so many instances where communication was not carried out correctly, where people didn’t recognize urgency, or when the patient wasn’t listened to, or the delay in reaction.”

Why are death rates higher among African American women? Here is one possibility:

Valerie Montgomery Rice, president and dean of the Morehouse School of Medicine in Atlanta, Georgia, believes that not only do bias and racism build up to affect the health of black women over time, but that stress from racism and poverty may have adverse effects as early as in utero or soon after a baby is born.

This is consistent with the effect of Trump administration attitudes towards immigrants on the health of Latinas and their babies, as I noted not long ago. 

And, of course, I have often noted that the former slave states of the south have the highest death rates in the country, and these are areas with high proportions of African Americans. Where you live still matters when it comes to your health.

Visualizing the Changing Urban Population

I happen to really like 3D maps. I think that they are terrific visualization tools, and so I was very pleased when Todd Gardner pointed us to a new set of such maps created by the Human Terrain project at Pudding, and yesterday summarized by Nick Routley at the Visual Capitalist. Here, for example, is the map for Dallas, Texas, showing the change in population at the local level between 1990 and 2015:

The green bars represent population increase over time, showing that the northern suburbs are where the metro area has. been growing. This helped explain to me why there is now a Frisco Bowl, where my San Diego State Aztecs will play the Ohio Bobcats next week. I've been in and out of Dallas many times over the years, but had not paid attention to those northern suburbs until I saw this map. And, while you might think that a 3D map should show a hole where there is population decline, these maps put the negative growth in red instead of green. Thus, you can see that the southern suburbs of Dallas have experienced a loss of population since 1990. My late father-in-law was born in Seagoville, just off the map below Mesquite, and I don't think he would be surprised at that demographic change.