RealClear Policy, June 8, 2021
Conventional wisdom has developed that the United States desperately needs more immigration to address the supposed twin evils of population aging and slowing population growth. The 2020 Census showing the U.S. grew by “only” 22.7 million over the last decade has prompted a new round of calls to expand immigration.
In fact, immigration does not make the population substantially younger unless the level is truly enormous and ever-increasing. Moreover, there is no body of research showing that higher rates of population growth necessarily make a country richer on a per-person basis. Advocates of mass immigration also ignore the downsides of larger populations, as well as the more effective and less extreme alternatives that exist for dealing with an aging society.
Despite this reality, Jay Evensen of Salt Lake City’s Deseret News argues that the slowdown in population growth revealed by the Census “portends a population disaster.” Bloomberg News’ Noah Smith thinks lower population growth creates a “grim economic future.”
Many commentators argue for increasing immigration above the more than one million already allowed in each year to spur population growth and “rebuild the demographic pyramid,” as former Florida Governor Jeb Bush famously put it in 2013. But as the former director of Princeton’s graduate program in population studies, Thomas Espenshade, observed a number of years ago, “the effect of alternative immigration levels on population age structure is small, unless we are willing to entertain a volume of U.S. immigration of historic proportion.”
To illustrate, the Census Bureau’s “low-immigration” scenario produces a U.S. population of 376 million in 2060, compared to 447 million under its “high-immigration” scenario — a 71 million difference. Under its low-immigration scenario, 56 percent of the population will be working-age (18-64) in 2060, compared to 57 percent under its high-immigration scenario. Thus, the addition of 71 million people raises the working-age share by just one percentage point.
One reason the impact is so modest is that immigrants are not uniformly young when they arrive — many now come in their 50s and 60s — and they grow old over time just like everyone else. Moreover, immigrant fertility now only slightly exceeds native-born fertility, and their children add to the dependent population — those too young or too old to work. Of course, these children eventually grow up and become workers, but by then many of their immigrant parents will be at or near retirement age.
Given the inefficiency of immigration as a tool to address population aging, immigration advocate Justin Gest at George Mason University is forced to propose unprecedented levels of future immigration to accelerate population growth and slow population aging. In a piece for CNN and a report for the immigration advocacy group fwd.us, he argues for doubling immigration to the United States to make the country “younger, more productive, and richer.”
Gest’s own projections show that the current level of immigration will make the U.S. population 74 million larger in 2050 than if there was no immigration, while doubling immigration would add another 92 million people by 2050.
Gest emphasizes that making the population 166 million larger increases the aggregate size of the economy significantly. More workers, more consumers, and more government spending does make for a larger GDP. But a larger population means the larger GDP is spread out over more people, so each individual is not necessarily better off. If all that mattered was the overall size of the economy, Bangladesh would be considered a richer country than New Zealand. Of course, what really determines the standard of living in a country is its per capita GDP.
Gest claims that the 74 million additional people that the current level of immigration would add will raise per capita income by 4 percent in 2050, relative to no immigration. He further asserts that doubling immigration would, along with an additional 92 million people, increase average income by another 3 percent. The idea behind this calculation is that if there are more workers — or more specifically, if a larger share of the population is of working-age — the average income of the entire population will be higher.
What is so striking about these numbers is that even if everything Gest argues is true, adding a total of 166 million people to the country — more than the combined populations of France and Germany — in just three decades only modestly improves per capita economic growth. But even this small increase is an overestimate if the new immigrants crowd out some existing workers from the labor force. There is certainly evidence that this happens with teenagers and Black Americans.
In the real world, it is hard to find evidence that population growth actually increases per capita economic growth. For example, if population growth were such an economic boon, then countries like Canada and Australia, which have among the highest rates of immigration and resulting population growth in the developed world, would dramatically outpace a country like Japan, which has relatively little immigration and a declining population. And yet, between 2010 and 2019, Japan’s per capita GDP growth was slightly higher than Canada’s and Australia’s. Among all developed countries, the correlation between population growth and per capita economic growth was actually negative between 2010 and 2019.
One of the reasons population growth is not associated with economic growth is that increasing the supply of workers reduces incentives to improve productivity. Looking across countries, a 2017 study by Ronald Lee and Andrew Mason found that “low fertility is not a serious economic challenge.” Instead, they find that “The effect of low fertility on the number of workers and taxpayers has been offset by greater human capital investment, enhancing the productivity of workers.” There is simply no reason to assume that a larger population will necessarily be richer.
Putting aside economics, making the population 166 million larger or even 74 million larger than it would otherwise be has important environmental implications. While population is not the only factor that determines human impact on the environment, it does have a direct bearing on everything from preventing further habitat loss to cleaning up the Chesapeake Bay.
One can debate the severity of climate change and how best to address it. But mathematically, if the total population is 166 million (50 percent) larger in 2050 than it would otherwise be, then each person would have to reduce their greenhouse gases admission by roughly one-third just to maintain the current level of emissions, to say nothing of lowering levels. As Joseph Chamie, the former director of the United Nations Population Division, pointed out in The Hill recently, stabilizing America’s population is necessary “to deal effectively with climate change and many other critical environmental concerns.”
In addition to the environment, making the population dramatically larger must also have profound implications for the quality of life. Most Americans aspire to live in areas with a fair amount of open space. A 2018 Gallup poll found, by a two-to-one margin, that Americans want to live in rural areas or suburbs. The rapid suburbanization of immigrants shows that they share this desire. Significantly increasing the nation’s population density is likely to make it more difficult for many Americans to live the way they want to.
There is also the issue of traffic. As a Brookings Institution analysis a number of years ago concluded, “The most obvious reason traffic congestion has increased everywhere is population growth.” Traffic congestion alone has been estimated to cost the American economy $120 billion annually. Both the American Society of Civil Engineers and the Department of Transportation have reported that the nation’s roads are in a state of disrepair and need significant upgrades. It is hard to imagine that adding tens of millions more people in just 30 years would not create even more congestion.
If we are concerned about population aging, there are far less radical ways to address it. Projections by Karen Zeigler and myself show that raising the retirement age by just one year increases the share of the population that is working-age (16-64) about as much as all of the immigration expected by the Census Bureau through 2050. Increasing it by three years improves it more than does doubling immigration. We also found that increasing the share of working-age people who have a job from the pre-Covid rate of 70 percent to 75 percent would do more to improve the overall share of the population who are actually workers in 2050 than would the current level of immigration.
Population boosters assume a larger population would be a boon to the economy, even though there is no clear evidence that this is the case. They also ignore the negative impact on the environment, congestion, traffic, and other qualify of life issues. There are more effective, less radical, and more environmentally sustainable ways to deal with the challenges associated with population aging than using an ever-increasing level of immigration to dramatically increase the population.