It’s been nearly 18 months since President Donald Trump took office and began to upend longstanding immigration policy in an effort to promote mass deportation.

The report from Boston Indicators, titled “An Uncertain Future: How the Immigration Crackdown Threatens Massachusetts’ Labor Force,” finds immigration to Massachusetts has slowed significantly. The report estimates that net international migration to Massachusetts fell by more than half during the first six months of Trump’s second term.

The federal crackdown on legally present and undocumented immigrants is beginning to impact several key industries — even as Massachusetts is increasingly dependant on immigration to sustain its labor force.

Support for GBH is provided by:

“One of the reasons Massachusetts is uniquely vulnerable to this immigration crackdown is that we rely on foreign-born workers both for high-skill industries and for low-skill industries,” said Luc Schuster, executive director of Boston Indicators, one of the two research organizations that published the report.

On one side, immigrants have a large presence, especially Haitians, in the nursing home and assisted care workforce, he said.

“But also immigrants have been critical to fueling our innovation economy and institutions of higher-ed. We have a disproportionate share of foreign-born workers at both ends of the spectrum in those sectors and the immigration crackdown that’s happening federally is slowing flows for workers in both sectors,” he said to GBH in an interview on Wednesday.

The report was co-published with MassINC Policy Center.

Beyond small-scale detentions mentioned in the report, the wider impact has come from the Trump administration curtailing pathways to legal immigration, such as with student visas; the new $100,000 fee for all H-1B applicants; and severing temporary protected status for Haitians and other immigrant groups.

Haitian workers have emerged as one of the clearest short-term labor force risks in the state given the health focused sectors many temporary protected status holders work in.

Support for GBH is provided by:

The report says Mass Senior Care Association estimates that 40% of nursing facility workers in Massachusetts are foreign-born, including roughly 2,000 frontline Haitian TPS workers.

For students and researchers, the impact of visa rules changes and fees, along with federal gutting of university research grants have had an enormous impact.

“Forty-two percent of Massachusetts scientists reported that researchers in their labs had relocated to other countries over the past year as a direct result of Trump administration policies,” researchers note in the report.

The drop in foreign-student enrollment at the state’s plethora of universities has been documented. The report predicts that if current trends continue, the state will lose $1.4 billion in economic activity from those students.

Complex work authorization changes, the pause on immigration document processing for immigrants from 39 countries (the so-called travel ban countries), limits on green card, asylum and naturalization applicants have all contributed to the decline in people who can live and work here legally and come from abroad.

The report reveals Massachusetts has the second lowest native-born birthrate in the country, with tens of thousands long-standing residents leaving to other states due to high costs. Many baby boomers are also aging out of the workforce, and researchers estimate that Massachusetts needs 60,000 new immigrants annually just to maintain the size of the state labor workforce.

A major resource for new workers in the coming years will be the children of existing immigrants in Massachusetts — at least a third will come from the state’s Gateway Cities.