Source: CENTER FOR IMMIGRATION STUDIES, 2/5/19

A new Center for Immigration Studies analysis of the Census Bureau's latest population projections shows that immigration will make the population much larger, but does not have a large impact on the share of the population that is of working age (16 to 64). The Bureau projects future population size, but does not discuss the role that immigration plays. By separately examining the impact of immigration on the Census Bureau projections, this new CIS report provides policymakers and the public with much-needed context.

"There is no question that, barring a change in policy, immigration will add tens of millions of people to the U.S. population over the next four decades," said Steven Camarota, the Center's Director of Research and lead author of the report. "But that increase in population will only modestly impact the ratio of workers to non-workers," he continued. "In contrast to immigration, a small increase in the retirement age can have a larger impact on the working-age share of the population without the consequences that may come from a much larger population, including for the environment and quality of life."

View the full analysis at: https://cis.org/Report/Projecting-Impact-Immigration-US-Population.

Among the findings:
• The Census Bureau projects that future net immigration (the difference between the number coming and number leaving) will total 46 million by 2060 and that total U.S. population will reach 404 million — 79 million larger than in 2017.
• Varying the immigration component shows that net immigration will add 75 million to the population, accounting for 95 percent of the increase by 2060.
• We can gain insight into immigration's impact by comparing the level projected by the Census Bureau to what would happen if immigration was reduced by two-thirds, which would roughly stabilize the U.S. population after 2040.
• Under a stabilization scenario, net immigration would total 16 million by 2060 (370,000 annually), producing a population of 354 million in 2060 — 50 million less than currently projected by the Bureau, but 29 million larger than in 2017.
• Many argue that without immigration there will not be enough workers to support the government or economy. Yet these projections indicate that in 2060, 59 percent of the population will be of working-age (16-64) compared to a quite similar 58 percent under the stabilization scenario.
• Looking at the ratio of potential workers (ages 16 to 64) relative to those of retirement age (65-plus) also shows the modest impact of immigration. Under the stabilization scenario there will be 2.2 workers per retiree compared to 2.5 workers assuming the Census Bureau's level of immigration.
• Immigration only modestly impacts aging, mainly because some immigrants do not arrive young and all immigrants age like everyone else, adding to the population that is outside of the working age.
• It is possible for immigration to maintain the current working-age share or ratio of workers to retirees, but it would require net immigration roughly five times the level projected by the Census Bureau through 2060. This would result in a total U.S. population of 706 million in 2060 — more than double the current population. 

Alternately, raising the retirement age two years, even assuming zero net immigration, has about the same impact on the working-age share or ratio of workers to retirees in 2060 as the level of net immigration projected by the Census Bureau.