By Tami Luhby, CNN

Already massively rich, American billionaires have seen their collective fortunes climb by more than 70% to more than $ 5,000 billion during the pandemic.

This is one of the reasons Congressional Democrats focused earlier this week on this elite group of around 700 people to help pay for their massive social spending package. They abandoned the proposal after in the face of resistance of several moderate members of the party.

The boom in the stock market helped boost billionaire net worth by more than $ 2 trillion from the onset of the pandemic through mid-October, according to a recent report by Americans for Tax Fairness and from the Institute for Policy Studies Program on Inequality, which analyzed Forbes data.

Their windfall came at the same time as Covid-19 was wreaking financial havoc on tens of millions of Americans, especially those from the lowest strata.

The wealth gains of billionaires over the past 19 months would be enough to pay for President Joe Biden proposal to strengthen the country’s social safety net, said Frank Clemente, executive director of Americans for Tax Fairness.

“And they would be as rich as before,” he said.

The number of U.S. billionaires also increased during the pandemic to 745, from 614 in March 2020, according to review of Forbes data by left-wing groups.

At the top of the list is Elon musk, CEO of Tesla and richest american. As of Thursday, his net worth had climbed more than 1,000% to nearly $ 274 billion as of March 18, 2020. The entrepreneur amassed his fortune through his Tesla shares and his controlling stake in privately held SpaceX, which he also directs.

Then Amazon founder Jeff Bezos with a net worth of $ 197 billion, up more than 74% since the start of the pandemic.

And to round out the top 3, Microsoft founder Bill Gates with a fortune of $ 38 billion that grew by 39%.

Tax billionaires

Democrats briefly turned to the billionaire tax after Arizona Senator Kyrsten Sinema scuttled their initial plans to pay off the budget reconciliation package by raising the corporate tax rate and increasing the the highest marginal rates of individual income and capital gains.

Oregon Senator Ron Wyden, chairman of the Senate Finance Committee, unveiled details of the complicated and controversial plan he has been working on for at least two years on Wednesday.

The proposal would have taxed billionaires on the appreciation of certain assets each year, instead of just at the time of sale, as is currently done. The rich often borrow from these assets to accumulate more wealth and finance their way of life, while avoid adding to their annual income tax.

The tax is said to have affected only about 700 people – those with more than $ 1 billion in assets or with reported income of more than $ 100 million for three consecutive years.

For marketable assets, such as stocks, billionaires would have paid a capital gains tax, currently 23.8%, on the increase in value and would have deducted losses each year.

Non-marketable assets, such as real estate and interests in businesses, would not have been taxed each year. Instead, the billionaires would have paid capital gains tax, plus interest charges, when they sold the stake.

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