In its most detailed look yet at the impact of immigration on the U.S. economy and budget, Congress’ budget office estimated the recent increase in documented and undocumented immigrants would both boost the economy and trim the budget deficit.

Immigration continues to be a hot-button issue on the presidential campaign trail, with the Republican candidate, Donald Trump, promising to begin “the largest deportation operation” in the history of the country as soon as he’s sworn in.

But if the nonpartisan Congressional Budget Office is correct, restricting immigration could mean larger deficits and a worse economy ahead.

Meanwhile, the U.S. Border Patrol said last month that daily arrests at the southern U.S. border dropped by more then 40% in the three weeks since President Joe Biden took steps to limit asylum claims by migrants.

“It’s pretty clear, based on the economic numbers, that the Biden-Harris administration and their policies have had a dramatic benefit to the economy and immigrants play a huge part of that,” Rep. Pete Aguilar (D-Calif.), the caucus chairman for House Democrats, told HuffPost.

“A lot of our colleagues on the other side of the aisle decry immigration policies, yet their regions and industries that they appreciate benefit from immigrant labor,” he said.

The CBO report, released Tuesday, largely reiterated conclusions first disclosed by the office in June in a small portion of its budget and economic update. But while that discussion was limited to only a few pages, the new report is more extensive.

The report compares estimates of how the economy and budget would be impacted by immigration rising by 8.7 million migrants from 2021 to 2026, CBO’s current forecast, against how the economy and budget would do if the same pace of immigration as before the COVID-19-fueled surge ― 200,000 people a year ― had continued instead.

It found that the increase in immigration would increase the size of the U.S. economy by about $8.9 trillion over the 2024 to 2034 period.

A bigger gross domestic product would mean more revenues for the government, both directly in taxes paid by immigrants but also simply from more economic activity. That $1.2 trillion over 10 years would be slightly offset, though, by about $300 billion in additional federal benefits payments paid out to immigrants and their children, as well as economic factors like higher interest rates, the CBO said.

Overall, that higher level of immigration would shrink the budget deficit by $900 billion overall through 2034, the CBO said. While $900 billion is a large number, it’s a tiny percentage of the $22 trillion deficit the agency projects the government will run between 2025 and 2034.

The CBO analysis did not include so-called discretionary spending, the amounts set aside each year for federal agencies outside of Social Security and Medicare, or the impact of immigration on state and local governments.

However, the CBO did say most studies have found that more immigration does lead to higher costs for state and local governments, as the costs for immigrants outpaces the additional money they add to the economy.