The Census Bureau is projecting that the population of the United States will hit 404 million by 2060, and nearly all of the net growth will be from immigrants and their families.

A new analysis of the figures shows that of the 79 million more in 2060, 75 million will be legal and illegal immigrants and their families, a population the size of France and Belgium combined.

Without immigration, according to the Census analysis from the Center for Immigration Studies, the U.S. population would increase by just 3.7 million, the latest sign that the country is on a path to zero native population growth.

"We find that varying the immigration component has a very large impact on the future size of the U.S. population. The Census Bureau projects net immigration of 46.4 million between 2017 and 2060, creating total a population of 404 million in that year — 96 million larger than in the last Census in 2010 and 79 million larger than in 2017. The addition is roughly equal to the combined populations of France and Belgium. Almost all (75 million) of the post-2017 increase is due to future immigration. That is, immigrants who have not yet arrived, but who will do so absent a change in policy, plus their descendants," said the report provided in advance to Secrets and released this morning.

Concerns that America won't produced enough new citizens on its own has alarmed some politicians who have advocated for expanding immigration so that there are enough younger workers to fill jobs in the figure.

But the CIS analysis, from Steven Camarota the Center’s director of research and lead author of the report, said that the age of the population won’t be significantly impacted, or lowered, from younger immigrants.

“There is no question that immigration will add tens of millions of people to the U.S. population in the next four decades, while only modestly impacting the ratio of workers to non-workers,” Camarota said.

Instead, he suggested that keeping people in the workforce longer by pushing retirement off would have a bigger impact.

“In contrast to immigration, a small increase in the retirement age can have a larger impact on the work-age share of the population, without the implications for the environment and quality of life that may come from a much larger population,” he said.

Camarota's report concluded, "The debate over immigration should not be whether it makes for a much larger population — it does. The debate over immigration should also not be whether it has a large impact on increasing the working-age share of the population or the ratio of workers to retirees — it does not. The key question for the public and policy-makers is what costs and benefits come with having a much larger population and a more densely settled country. Some foresee a deteriorating quality of life with a larger population, including its impact on such things as pollution, congestion, loss of open spaces, and sprawl. Others may feel that a much larger population will create more opportunities for businesses, workers, and consumers. These projections do not resolve those questions. What the projections do tell us is where we are headed as a country in terms of the size and density of our population. The question for the nation is: Do we wish to go there?"