Migrant Worker
A migrant laborer weeds a melon field during the early morning in Somerton, Arizona, June 7, 2006. Reuters

Immigrants will play the largest part in the growth of the American economy in the next 20 years, according to a report from the Pew Research Center released Wednesday. This is because Baby Boomers — those born between World War II and 1965 — are heading into retirement, and for the economy to continue to grow, immigrants will have to be the ones to replace them.

The report was published during a time when the future for many immigrants in the U.S. looked precarious. A few days earlier, President Donald Trump had announced his newest iteration of his temporary immigration ban. The January ban blocked immigrants and travelers from six Muslim-majority nations for 90 days, and it temporarily stopped refugees from entering the U.S.

Trump has also touted his plans to build a wall along the U.S.-Mexico border to halt illegal crossings.

Read: How Trump Creates Fake News About Immigrants

But according to the Pew study, America will need immigrants for its workforce to grow.

Pew researchers estimated that the number of adults in their prime working age — 25 to 64 years old — will rise from 173.2 million in 2015 to 183.2 million in 2035. Athough those numbers may sound high, compared to the past, that growth rate is actually quite low. If the U.S. workforce wants to keep growing, "perhaps the most important component of the growth in the working-age population over the next two decades will be the arrival of future immigrants,” the Pew report stated.

Read: As Unions Shrink, Liberals Advocate For Organized Labor

More and more immigrants of working age are expected to come to the U.S. over the next 20 years. The number of working-age immigrants was 33.9 million in 2015, and it’s expected to grow to 38.5 million by 2035, according to current projections.

Here’s the rub: If the projections don’t pan out, then the number of working-age immigrants would drop by 17.6 million in 2035. And that would have a rather large effect on the U.S. labor force. Instead of growing, the the number of U.S. workers would fall to 165.6 million.