One provision tucked into the federal economic-rescue law increases the amount of deductions companies are permitted to take on the interest they pay on large quantities of debt. Only companies with at least $25 million in annual receipts can qualify for that break.

Another change lets people deduct even more of their businesses’ losses from any winnings they reaped in the stock market, sharply reducing what they owe in capital gains taxes. Only households earning at least $500,000 a year — the top 1 percent of American taxpayers — are eligible.

And yet another provision in last month’s rescue package allows companies to deduct losses in one year against profits that they earned years earlier. The tax break most likely won’t put any extra cash directly into the hands of companies hit by the current crisis for at least a year.

The bottom line is that, barely two years after congressional Republicans and President Trump lavished America’s wealthiest families and companies with a series of lucrative tax cuts, those same beneficiaries are now receiving a second helping.

Many of the tax benefits in the stimulus are “just shoveling money to rich people,” said Victor Fleischer, a tax law professor at the University of California, Irvine. While the 2017 tax-cut package was a bonanza for big companies and wealthy individuals, in order to keep the law’s overall costs down it imposed a number of restrictions on who could take advantage of certain tax breaks and how much those taxpayers could reap.