This blog is intended to go along with Population: An Introduction to Concepts and Issues, by John R. Weeks, published by Cengage Learning. The latest edition is the 13th (it will be out in January 2020), but this blog is meant to complement any edition of the book by showing the way in which demographic issues are regularly in the news.

You can download an iPhone app for the 13th edition from the App Store (search for Weeks Population).

If you are a user of my textbook and would like to suggest a blog post idea, please email me at:

Thursday, October 27, 2016

Non-Human Animals Are Declining in Number--Humans Are to Blame

The World Wildlife Federation and Zoological Society of London have just released the latest Living Planet Report (the 2016 version), and its conclusions are dismal, at best. The Independent has this headline: "World facing first mass extinction since the dinosaurs as wildlife populations plunge by 67 per cent in 50 years" and a very nice illustrative video to go with that. The BBC is a little more reserved in its coverage, but there is nothing encouraging here.
The figures suggest that animals living in lakes, rivers and wetlands are suffering the biggest losses. Human activity, including habitat loss, wildlife trade, pollution and climate change contributed to the declines.
Dr Mike Barrett. head of science and policy at WWF, said: "It's pretty clear under 'business as usual' we will see continued declines in these wildlife populations. But I think now we've reached a point where there isn't really any excuse to let this carry on. "We know what the causes are and we know the scale of the impact that humans are having on nature and on wildlife populations - it really is now down to us to act."
The BBC science writer notes that there are criticisms of the methods used in the report, since many parts of the world don't have good data on animal populations. But even taking those limits into account, the animal population is in decline, we are the cause, and this is not a good thing. 

Wednesday, October 26, 2016

Migrants Dying in the Mediterranean are Mainly from sub-Saharan Africa

The civil war in Syria has produced a huge mass of refugees, but Europe's deal with Turkey to bottle them up in Turkey seems to be stemming that flow toward Europe, at least for the time being. In the meantime, however, migration out of Sub-Saharan Africa has generated a new round of deaths in the Mediterranean. Huffington Post reports that trying to cross the Mediterranean is three times more deadly this year than last year.
The death toll on the Mediterranean has nearly matched that of all last year, with more than 3,740 migrants and refugees having drowned on their way to Europe, and perilous winter months still to come, aid agencies said on Tuesday.
Smugglers are now sending thousands of people on flimsy inflatable rafts from Libya to Italy in mass embarkations, perhaps to lower their own risks of being caught, but also complicating the work of rescue teams, they said.
You have to go to other sources, however, such as a recent story in the Economist, to realize that these migrants have little to do with the conflict in the Middle East. Rather, they are leaving the rapidly growing countries of Sub-Saharan Africa, especially Nigeria. Think about this: Nigeria is currently the 7th most populous nation in the world, but it is on track to surpass the U.S. by the middle of this year and become the 3rd most populous country, thanks to a birth rate that is currently at 5.5 children per woman. Its economy is heavily dependent upon oil and the drop in oil prices has generated economic problems throughout Nigeria (maybe not as bad as in Venezuela, but still bad). What to do? Head to Europe, that's what. Nigerians have been arriving in Italy without documents for a long time, but the pace is picking up, and it isn't clear that it will slacken any time soon.

Tuesday, October 25, 2016

China Consumes More Pork, and Latin Americans Pay the Environmental Price

I've written before about the environmental impact of feeding more people, especially in China, the world's most populous country and second largest economy. A new report out from Boston University tries to gauge this impact on Latin American and Caribbean (LAC) countries. China has become a huge trading partner with Latin America, but China mainly buys agricultural and mineral resources, while selling manufactured goods. As the report notes, this is essentially a backward step for Latin America.

LAC is, in effect, exporting water and importing carbon. Overall, LAC’s boom in exports to China has driven the region’s production into carbon- and water-intensive sectors. At the same time, LAC’s boom in imports from China has further increased the region’s environmental footprint on both fronts.
Contrary to the hypothesis of the environmental Kuznets curve, primary production is more environmentally sensitive than manufacturing in LAC: it creates more net greenhouse gas emissions and uses or contaminates more water per million dollars. So it is not surprising that LAC exports to China are more environmentally sensitive than other LAC exports. Given these risks associated with this important new economic relationship, LAC governments would be wise to approach it with reinforced emphasis on setting environmental safeguards that meet the needs of their development strategies.
Although the focus of the report is not on any specific Latin American country or countries, we in the U.S. are obviously especially interested in Mexico. One of the features of the current presidential campaign in the U.S. is Donald Trump's insistence that NAFTA was one of the worst trade deals ever signed. Admittedly, it didn't turn out as well as expected, but that was not the fault of those who designed the deal. I was one among many demographers who testified before Congressional committees and caucuses back in 1993 as Congress was debating the bill. My recollection is that we were all in agreement that good jobs in Mexico would raise wages in that country, thus cutting down migration to the U.S., while also offering cheaper goods for sale in the U.S.--a genuine win-win. NAFTA was, however, undermined by the fact that East Asian countries (principally China and South Korea) offered companies even lower wages than were prevailing in Mexico, and jobs wound up going to Asia rather than Mexico. My sense is that these global dynamics are not well understood by the current crop of American politicians.

Monday, October 24, 2016

It's the Demography, Stupid!

Thanks to my son, John, for linking me to a story from yesterday's Financial Times with the provocative title of "It's the Demography, Stupid," drawing upon Bill Clinton's successful campaign slogan from many years ago that "It's the Economy, Stupid." The article itself is mainly about the effect of demographic change (especially aging) on the interest rate--more specifically, on the "equilibrium interest rate (r*)". 
Why is there a link between r* and demography? Remember that the equilibrium real rate of interest is that which ensures that savings and investment in the economy are equal in the long run. If ex ante savings exceed investment, r* declines, and vice versa. Since the savings behaviour of households is clearly affected by the age distribution of the population, and the investment behaviour of the corporate sector is affected by the labour supply, it is obvious that demography matters a lot for the determination of r*.
Now, I admit that I did not remember what the equilibrium real rate of interest was, so that was my lesson for the day. Life has also taught me that when economists talk about "equilibrium" we should probably stop listening, but in fact that is because demographic change does indeed make equilibrium an elusive concept. The economy needs to adapt to demographic change, rather than pretending that it does not exist, and the author of this story--Gavyn Davies (a British economist)--is pushing that agenda. If you have read my book, you know my belief that demography underlies almost everything that happens in the world, in one way or another. The more of us who understand that, the better off the world will be.

Friday, October 21, 2016

Geography, Demography, and the Presidential Election

You may already have seen this map because it has been making the rounds on the internet, but it tells the story of the geography and demography of the Presidential election. To be sure, the map reflects voting at the county-level for the 2012 contest between Obama and Romney. But this is the road map for the current Clinton - Trump election:

The map was put together by Nate Cohn and Toni Monkovic of the Upshot feature of the NYTimes, and the two of them have a great discussion about what this all means. Here's a snippet:
Toni One way to understand Blue America is to follow the water. The oceans, the Great Lakes and the major rivers were obvious places for small settlements to become major cities. And these big metro areas are where Democrats dominate.The population of rural counties as a whole has been declining, and metro areas are growing. Over time, this will help Democrats, no?
Nate The Democrats do tend to do best in metropolitan areas. All of the major demographic and cultural changes that have helped the Democrats over the last decade are concentrated in these diverse and often well-educated areas. In this election, I’d guess Hillary Clinton will fare even better in metropolitan areas than President Obama did.
The red parts of the country tend to be rural, predominantly white, less-well educated--Trump country. The blue parts in the southern states reflect counties that historically had plantations with large slave populations and they are still predominantly African-American. Blue areas in Texas, New Mexico, and Arizona are counties with high percentages of Latinos and/or Native Americans. Blue counties along the two coasts reflect the better-educated urban populations--these tend to be Clinton country.

Wednesday, October 19, 2016

Habitat III Underway in Ecuador: Can Cities Become More Sustainable?

This week has witnessed a huge gathering in Quito, Ecuador called Habitat III--the Third United Nations Conference on Housing and Sustainable Urban Development. Almost all of the world's population growth is showing up in cities and will continue to do so for the foreseeable future. This is due to the combination of migration out of rural areas (where jobs aren't increasing as fast as the population) and natural increase in cities (where even relatively low births in developing countries still generate an excess of births over deaths). The focus is obviously on cities in developing countries because they have the most fragile infrastructure and are increasing at the most rapid rates. The U.S. State Department's project on Secondary Cities will be on display at the meetings, emphasizing the complexity of urban life.

When I think of urban sustainability, I'm first concerned about the basics--getting a consistent supply of food and clean water to people, coupled with good sewerage and electricity--all associated with adequate housing structures and low levels of ground, water, and air pollution. But the "New Urban Agenda" of the UN goes beyond that to incorporate improvements in the quality of social and economic life in cities. Indeed, the limited coverage in the media of the event seems mainly to have focused on those urban residents who feel disenfranchised from the mainstream of urban life. 

In truth, we are getting very close to the point at which urban life is mainly what human existence is all about. So, we are not just studying cities--we are really studying the evolution of human society. If cities cannot be sustained in every way, then human society is sunk.

Monday, October 17, 2016

Middle Age Comes Earlier in Young Countries

Middle age is usually thought of as an individual characteristic and is generally defined as that period of time between youth (however you define that) and old age (however you define that). But there is an aggregate perspective, as well, as Marilyn vos Savant (reportedly the world's smartest woman--I'm not making that up!) pointed out in this week's Parade magazine (a ghost of its former self, but it still shows up in the Sunday paper). It is reasonable to define "middle age" as that age at which half of the population is younger and half older (otherwise known as the median age). By that definition, the middle is a lot younger in developing countries with high fertility than in countries with low fertility. We know this because birth rates are the principal driver of the shape of the age structure. So, in the West African country of Niger, which I noted a few years ago had the world's "worst" demographics,  and where women are having a whopping 7.6 children each, the median age is 14.8 years. Uganda, Chad, and Angola are close to that.

At the other end of the extreme is Japan, where the median age is pretty close to what we think of as "middle age" at the personal level--46.5, and where women are having only 1.5 children each. Close to Japan are other low-fertility countries including German, Italy, and Portugal. The United States is several years lower at 38 years, whereas the world average is 29.6, which is almost exactly half way between the youngest and oldest median ages. These data, by the way, come from the Population Division of the United Nations, and they are consistent with what Marilyn vos Savant used in her short piece, so it is good to know that the smartest woman in the world understands where to go for demographic information.

Sunday, October 16, 2016

Gases That Cool Us and Our Food Heat Up the Planet--We've Got to Stop These Guys!

...And a new global treaty is aimed at doing just that. Yesterday in Kigala, Rwanda, 170 nations reached a legal agreement to cut the use of hydrofluorocarbons (HFCs)--gases that are used extensively in refrigeration and air conditioning. As the NYTimes notes:
HFCs are just a small percentage of greenhouse gases in the atmosphere, but they function as a sort of supercharged greenhouse gas, with 1,000 times the heat-trapping potency of carbon dioxide.
The Kigali deal was seven years in the making, and is a compromise between rich nations and poorer, hotter ones, including some where rising incomes are just starting to bring air-conditioners within reach. Wealthier nations will freeze production of HFCs more quickly than poorer countries, though some nations, including those in Africa, elected to phase the chemicals out more rapidly than required, citing the grave threats they face from climate change.
Refrigeration and air conditioning have been around for only a few decades--within my lifetime, but they have revolutionized how and where we live. This wouldn't be a huge problem for the planet except for the fact that the population has tripled in size over this period of time, and almost everyone has more income than they used to. This latter point is a good thing in the abstract, but it means that the demands on resources have been growing even faster than the population, leading to the global worry about key side-effects such as global warming. 
The deal is an amendment to the Montreal Protocol, the landmark 1987 pact designed to close the hole in the ozone layer by banning ozone-depleting coolants called chlorofluorocarbons, or CFCs. That means the Kigali amendment maintains the legal force of a treaty, even if that treaty was ratified by the Senate during the Reagan administration.
Chemical companies responded to the 1987 agreement by developing HFCs, which do not harm the ozone layer but do trap heat in the atmosphere.
Fortunately, the chemical industry appears to be on board, and so there is a lot of work going on to find appropriate substitute for HFCs.
Top officials from the chemical industry were in Kigali to push for the deal. “Our industry is hard at work doing the research on the HFC alternatives,” said Stephen Yurek, the chief executive of the Air-Conditioning, Heating and Refrigeration Institute, an advocacy group. “Getting that right is certainly as important as reaching agreement.”
This is all very encouraging, especially in the current political environment where there are so many people who seem to want to deny that climate change is happening or, at the least, that humans have anything to do with it. 

Wednesday, October 12, 2016

Supreme Court Case on Racial Bias Is All About Jury Demographics

This week the U.S. Supreme Court heard arguments in the case of Peña-Rodriguez v. Colorado. NPR gives us the background, the essence of which is this: An Hispanic man in Colorado was accused in 2010 of molesting two girls at a race track where he trained horses. Although one of his co-workers testified that he was elsewhere at the time, he was nonetheless convicted of misdemeanor charges (albeit not the more serious felony charges) by a jury that apparently was influenced by one of its members who was a former policeman and clearly had racist views:
With the trial judge's permission, the lawyers then obtained affidavits from the jurors, in which the jurors quoted H.C. as saying that, from his experience as an ex-policeman, he knew that the defendant was guilty "because he's Mexican" and "Mexican men ... think they can 'do whatever they want' with women," and that where he used to patrol, "nine times out of ten Mexican men were guilty of being aggressive toward women and young girls."
The affidavits also quoted H.C. as saying that the alibi witness was not credible because, among other things, he was "an illegal."
In fact, the witness had testified at trial that he was a legal resident of the United States.
Mr. Peña-Rodriguez appealed his sentence to the Colorado Supreme Court, which turned him down on the grounds that jury deliberations cannot be part of the appeals process. So, he took the case to the U.S. Supreme Court which seemed to look favorably on his argument and it seems at least possible that that they will reverse the conviction.

All of this probably would have been avoided had there actually been a jury of his peers in the courtroom in Arapahoe County, Colorado. I've been looking at these issues for a long time, as I've noted before, and using data from IPUMS-USA, provided by the University of Minnesota Population Centers, I just calculated that in 2010 the percent of the jury-eligible population of that county  (i.e., 18 or older, a U.S. citizen, who speaks English well) that was Hispanic was 10%. Thus, at least one of the jurors should have been Hispanic, had this truly been a jury of his peers. And, of course, had there been an Hispanic on the jury, the racist comments probably would not have been uttered, Mr. Peña-Rodriguez might have been acquitted, and SCOTUS could have been saved a lot of time and trouble.

Tuesday, October 11, 2016

Haiti Faces Yet Another "Plague" of Cholera

It isn't easy being the poorest country in the western hemisphere even on a good day, but Haiti has had some really bad days over the past several years. First came the disastrous earthquake in 2010, from which the country has never really recovered, and then came cholera in its wake, as a I noted at the time:
Although it has not yet been confirmed, there is suspicion that cholera was brought to Haiti by Nepalese peace-keepers working with the United Nations. All cases have occurred downstream from the camp in which they are based and it is believed that human excrement (the mode of transmission) has been dumped in the nearby river.
Unbelievably, it took six years--until August of this year--for the UN to admit that it had anything to do with the cholera in Haiti, and it has not yet done much to help the situation of victims and their families. And, of course, that was all before this past week's passage of Hurricane Matthews through the Caribbean. CNN reported that:
Haiti's leader says Hurricane Matthew's assault has accelerated the already existing cholera epidemic and undermined the strides made in fighting the disease. "A lot of effort has been made to avoid the spread of this epidemic," said Interim President Jocelerme Privert, "but the hurricane has accelerated it."
Thirteen people have died from cholera since Matthew hit Haiti, he said. This tragedy -- which has killed more than 370 people -- comes after a devastating cholera outbreak in 2010. The United Nations says it has been involved in trying to eradicate the disease in Haiti. 
Cholera, which is spread through water or food contaminated with Vibrio cholerae bacteria, can cause severe diarrhea and vomiting, which leads to extreme dehydration. It can swiftly result in outbreaks, and patients who are not treated quickly can die within hours. 
Haiti has one of the highest rates of cholera in the world, with almost 10,000 people dead from the disease since 2010 and more than 27,000 suspected cases have been reported this year -- an estimated 1 in 3 of them children, UNICEF said.
Keep in mind that there were no known cholera cases in Haiti before the UN peacekeepers came in after the 2010 earthquake. So, the fact that it now has "one of the highest rates of cholera in the world" is a tragedy on top of a tragedy.

Monday, October 10, 2016

Getting the Bigger Picture Through Spatial Modeling of DHS Data

A tweet today from Springer Publishing noted that the latest issue of Spatial Demography is "on the newsstands" and I am co-author on a paper in this issue. I wouldn't necessarily toot my horn on something like this, but the methods we used in the paper presaged a new effort by the DHS Spatial Data Repository team to create spatial models of data from the DHS surveys. Our work was led by one of our PhD students, Stephen Crook, and utilized Empirical Bayesian Kriging, the same method employed by the DHS folks. We focused on a four-region area of southern Ghana and examined the spatial patterns of obesity in that country. DHS data have consistently shown an increase in obesity over time in Ghana (and many other African countries), particularly in the urban areas where there is increasing access to Western-style processed foods. Here is what our map looks like, using data from the 2008 DHS (the 2014 data weren't out yet when we started working on this):

The hot spots are especially Accra (the capital and largest city in the country) in the south, and Kumasi to the northwest of Accra. Kumasi is the nation's second largest city. In particular, the data suggest that the suburban and peri-urban areas of Accra--where the wealthiest residents live--are especially prone to obesity. If you just analyze the DHS data without reference to the spatial patterning, you might get hints of what's going on, but the maps genuinely enhance our understanding.

Thursday, October 6, 2016

Could Humans Live Past 122 Years?

Every species on earth has a life span--an oldest age to which one of its members is known to have lived. Notice that I worded that carefully. We are talking about a verified oldest age of one member of the species (whether a human, a dog, a whale, or a redwood tree). The current record holder among humans is a French woman, Jeanne Clement, who died in 1997 at the age of 122 years, as I note in Chapter 5 of my text. I bring this up because a two-page letter published this week in Nature has received a surprising amount of publicity and even pushback, leading to a discussion about it yesterday in Nature and also in yesterday's NYTimes. Here's the deal:
An analysis of global demographic data published in Nature suggests that humans have a fixed shelf life, and that the odds of someone beating Calment’s record are low — although some scientists question this interpretation. They say that the data used in the analysis are not unequivocal, and that the paper doesn’t account for future advances in medicine.
The data in question come from the Human Mortality Database originally developed at UC Berkeley by John Wilmoth, who is now Director of the Population Division of the UN. That project was undertaken in collaboration with the Max Planck Institute for Demographic Research in Germany, where the data are now housed. Jan Vijg, a geneticist at Albert Einstein College of Medicine in New York City and two of his graduate students, "reasoned that if there’s no upper limit on lifespan, then the biggest increase in survival should be experienced by ever-older age groups as the years pass and medicine improves. Instead, they found that the age with the greatest improvement in survival got steadily higher since the early twentieth century, but then started to plateau at about 99 in 1980. (The age has since increased by a very small amount)."

The data suggest that the odds are pretty slim of living past 115 (you can get a quick shot of similar data at this website of record holders). Jeanne Clement is clearly an outlier, but at the same time she redefined upward what the human life span really is. Could someone live longer? My view is yes, but the chances are clearly slim. That seemed to be Vijg's reasoning also, and if you've read my book, you know that I agree with his view that we should spend our time and resources increasing human health span (the number of healthy years we live) rather than on thinking that we can somehow increase the maximum age to which a single human could live.

Tuesday, October 4, 2016

Polish Women Take to the Streets Over Abortion

Poland already has one of most restrictive set of abortion rules in Europe, but the country's legislature is trying to make it even harder for women to get an abortion. The BBC reports on this, as follows:
If the law - which has cleared one parliamentary hurdle so far - goes through it will make Poland's abortion laws as restrictive as those in two other countries in Europe: Malta and the Vatican.
Women found to have had abortions would be punished with a five-year prison term. Doctors found to have assisted in an abortion would also be liable for jail time.
The Catholic Church appears to be the primary pusher of this legislation, but women have taken to the streets to protest--most to protest against the proposed legislation, but some to protest the protesters.
Abortion is already banned in most circumstances in Poland. The current exceptions are:
* where the woman's life is in danger
* where there is a risk of serious and irreversible damage to the fetus
* where the pregnancy is as a result of rape or incest - this must be confirmed by a prosecutor
So, the new law would take away those exceptions. These are the kind of issues that have cropped up regularly in the United States and so it was not surprising that abortion was on the table, so to speak, at tonight's vice-presidential debate between Tim Kaine and Mike Pence. Although Catholic and personally opposed to abortion, Kaine argued that women need to be able to make the decision about an abortion which, after all, is legal in the U.S. Pence thought otherwise. It still astounds me that men really think they should make reproductive decisions for women. We still have a long way to go.

UPDATE: The protests did, in fact, cause Poland's legislature to rethink this legislation and it was voted down.

Saturday, October 1, 2016

Breastfeeding vs Baby Formula Pops Up as an Issue in Egypt

Many years ago Nestle and other companies that make baby formula were tried in the court of public opinion for pushing formula onto mothers, even though they had to know that breast-feeding is almost always better for the child. The world then pivoted back to encouraging new mothers to breast-feed for several months after birth. It seems, though, that the pivot wasn't quite so big in Egypt and that has created a fresh controversy in that country, as reported in a Public Radio International story pointed out to me by Debbie Fugate. The Egyptian government is struggling to stay afloat and so it has lowered its subsidy of baby formula, creating a supply problem for mothers that has caused a lot of consternation. The government has also implemented a very unusual test for mothers to confirm that they are not producing sufficient breast milk and thus need the formula.
New mothers in hospitals were the first to get the exams last month, intended to prove their need for extra milk. This measure symbolizes, some say, a depraved regime that disrespects women.
But why is there such a demand for formula?
“There is a need to better inform mothers and communities on the importance of breastfeeding for their child’s survival and mental and physical development,” said Bruno Maes, UNICEF’s Egypt representative. The agency says fewer than one-third of children in Egypt aged 4 to 5 months are exclusively breastfed. 
“The formula companies have done too good a job in marketing their product,” said Salma Ramadan, a pediatrician at Helwan General Hospital. “Many new mothers are not interested in hearing what we have to say about breastfeeding and start asking for the cans of subsidized milk even before they give birth.”
The 2014 Demographic and Health Survey in Egypt showed that stunting was apparent in children under the age of 6 months. It also shows that almost all Egyptian mothers breastfeed their babies, but a high proportion also supplement breastfeeding with baby formula very early on. Most mothers are apt to prefer that convenience, but it may not be beneficial either for the baby or for the current economy.