America’s billionaires made tremendous wealth gains during the pandemic, topping 55% or $1.6 trillion, according to a new analysis of Forbes data from two think tanks, who call the trend “troubling.”

“Billionaire wealth growth has perversely accelerated over the 13 months of global pandemic. But the piling up of fortunes at the top has proceeded at a rapid clip for decades even as the net worth of working Americans lagged and public services deteriorated,” according to a recent report.

Whether measured over 13 months or 31 years, the growth of U.S. billionaire wealth “is both astounding and troubling,” according to a new analysis of Forbes data from left-leaning think tanks Americans for Tax Reform (ATF) and the Institute for Policy Studies (IPS). Both groups support President Biden’s proposed corporate tax increases and his plan to tax wealthier households with $400,000 or more in annual income.

Between March 18, 2020, and April 12, 2021, the collective wealth of American billionaires increased from $2.95 trillion to $4.56 trillion, a 55% leap, “Billionaires” reported. “The increase in billionaire wealth alone could pay for nearly 70% of the 10-year, $2.3 trillion cost of President Biden’s proposed jobs and infrastructure plan—the American Jobs Plan,” according to the report.

“Congress should act to restore taxes on the wealthy and limit further democracy-distorting concentrations of wealth and power,” Chuck Collins, Director of the Program on Inequality at IPS said in a statement.  “This pandemic billionaire wealth surge is a grotesque milestone after three decades of wealth steadily flowing to the top.”

The wealth boom helped create six American “centi-billionaires”—individuals each worth at least $100 billion--as of April 12. “That’s bigger than the size of the economy of of 13 of the nation’s states,” the report said. Here’s how the wealth of the six ultra-billionaires grew during the pandemic:

Billionaires’ significant pandemic-era wealth expansion comes on top of a 19-fold increase in billionaire wealth over the past 31 years—from an inflation-adjusted $240 billion in 1990 to $4.65 trillion in 2021, the report stated.

According to the analysis, more than a third of the $4.3 growth in billionaire wealth from 1990 to today was created amid the past 13 months of the pandemic.

“It’s not just during the pandemic—billionaires have been running up the score on average Americans for decades,” Frank Clemente, executive director of Americans for Tax Fairness, said in statement. “The way to reverse this trend is by making sure the wealthy, and the corporations they own, start paying their fair share of taxes. President Biden is proposing to do just that so we can finally build an economy that works for working families.”

In a move that made headlines across the globe, Bezos climbed aboard the Biden tax train last week. “We support the Biden Administration’s focus on making bold investments in American infrastructure. We look forward to Congress and the Administration coming together to find the right, balanced solution,” he said in a statement on Amazon’s website.

Critics of Biden’s Keynesian economics and the wealth tax and distribution plans touted by some Democrats, however, think the new taxes may cripple the rebounding U.S. economy, U.S. competitiveness and the stock market, which could harm job creation and stifle middle class wealth creation, raises and benefits.

“The tax proposals in the American Jobs Plan (Biden infrastructure plan) rely on mistaken assumptions about how corporate taxes work, how corporations respond, and how workers are affected,” Erika York an economist with the nonpartisan Tax Foundation said in a recent blog.

According to York, an increase in the federal corporate tax rate to 28% would raise the U.S. federal-state combined tax rate to 32.34%, higher than every country in the OECD, the G7, and all our major trade partners and competitors including China “This would harm U.S. economic competitiveness and diminish our role in the world,” York said.

When the U.S. last had the highest corporate tax rate in the OECD, prior to tax reform in 2017 with the Tax Cuts and Jobs Act (TCJA), “the U.S. experienced several years of economic malaise, including chronically low levels of investment, productivity, and wage growth, as well as major distortions and avoidance schemes in the corporate sector. This included corporate inversions to lower-tax countries, migration out of the corporate sector and into the noncorporate sector, and a decline in business dynamism. This is why the U.S. lowered the corporate tax rate, to compete with other countries around the world that lowered theirs long ago,” York said.

Whether the Tax Foundation analyzes corporate tax collections as a portion of GDP, average effective tax rates, or marginal tax rates, “each measure shows that the U.S. effective corporate tax burden is close to or above the average compared to its OECD peers,” York added. “Raising corporate income taxes would put the U.S. at a competitive disadvantage, whether one looks at statutory tax rates or effective corporate tax rates,” she added.