The Trump administration’s plan to cut the workforce of the Internal Revenue Service in half and gut enforcement efforts could enable the richest people in the United States to evade an additional $30 million in taxes per day on average, according to an analysis published Monday on the eve of the nation’s tax filing deadline.

The analysis by the humanitarian group Oxfam America notes that the firing of 50,000 IRS employees—roughly half the agency’s staff—would “hurt ordinary people through slower refunds and customer service, while allowing wealthy tax cheats to pocket billions of dollars.”

Oxfam cites a recent study by the Yale Budget Lab estimating that the richest 1% in the U.S. are responsible for around 30% of the nation’s unpaid taxes. If the IRS were to lose 50,000 employees, the Yale Budget Lab found, the agency’s diminished capacity would result in $395 billion in lost federal revenue over a 10-year period—with the top 1% responsible for $30 million a day.

“While the rest of us dutifully file our taxes, ultra-wealthy tax cheats drain over a half a billion a day from the public coffers,” Rebecca Riddell, Oxfam America’s senior policy Lead for Economic and Racial Justice. “By seeking to gut the IRS, President Trump and Elon Musk would make it harder to fight poverty but even easier for the very richest taxpayers to avoid paying what they owe. This would undoubtedly be great for billionaire tax cheats but bad for everyone else.”

“President Trump and Elon Musk’s IRS cuts are part of a broader plan to further rig the tax system to favor billionaires and corporations.”

Attacks on the chronically underfunded and short-staffed IRS by the Trump administration and its so-called Department of Government Efficiency are already “tempting taxpayers to cheat,” according to reporting by Bloomberg last month.

The administration is also reportedly taking aim at the Justice Department’s Tax Division, another possible gift to the ultra-rich.

“When you combine this with the gutting of IRS itself, it basically means a radical diminution of tax enforcement in the United States,” Josh Marshall of Talking Points Memo wrote last week. “If you make more than, say, a million dollars a year, paying taxes is probably going to be voluntary going forward. It’s a new feature of billionairedom.”

The administration’s slashing of IRS staff, as well as Republican lawmakers’ efforts to yank funding from the agency, are expected to further reduce audit rates, particularly for the rich—whose returns are typically more expensive to probe.

But Oxfam America noted Monday that research shows “every $1 spent auditing the top 0.1% yields $6.29 in direct revenue, with total returns likely far higher due to greater deterrence.”

“President Trump and Elon Musk’s IRS cuts are part of a broader plan to further rig the tax system to favor billionaires and corporations,” the group said. “Congress should not only invest in the IRS but also reject efforts to have ordinary people pay for tax handouts to the ultra-rich.”