The 6 richest Americans are worth more than the GDP of 13 US states combined, including Delaware, Maine, and Hawaii

• According to Forbes, six Americans are worth more than $100 billion, making them centibillionaires.
• Their combined fortune of $815 billion is just over the collective GDP of the US' 13 poorest states.
• Amazon CEO Jeff Bezos is worth nearly $200 billion, beating the 2020 GDP of Utah.

America's richest keep getting richer.

The six richest Americans are worth more than the GDP of 13 states combined, including Delaware, Maine, and Vermont, according to data from Forbes and the US Department of Commerce.

The publication's rich list contains six "centibillionaires" - people worth at least $100 billion each.

In a new report, the Institute for Policy Studies (IPS) and Americans for Tax Fairness (ATF) said this meant that individually, each of the centibillionaires had a net worth bigger than the GDP of each of the 13 poorest US states.

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But calculations by Insider show that, collectively, these six centibillionaires have a collective fortune bigger than that of the 13 states combined.

Amazon CEO Jeff Bezos, Tesla CEO Elon Musk, Microsoft co-founder Bill Gates, Facebook CEO Mark Zuckerberg, Berkshire Hathaway CEO Warren Buffet, and Oracle founder and chairman Larry Ellison have a combined fortune of around $815 billion, per Forbes data from April 12.

This is just over the combined GDP of the 13 poorest US states, according to 2020 data from the US Department of Commerce: Hawaii, New Hampshire, Idaho, Delaware, West Virginia, Maine, Rhode Island, North and South Dakota, Montana, Alaska, Wyoming, and Vermont.

Bezos is worth nearly $200 billion - just over the 2020 GDP of Utah.

Vermont has the lowest GDP of all the US states, at $32.8 billion in 2020, followed by Wyoming and Alaska, though this is largely due to their small populations.

Mississippi has the lowest GDP per capita, at $38.5 billion. It has high levels of poverty and a low median income, in part caused by its historic reliance on cotton agriculture.

The ATF and IPS also found that over the last 13 months, American billionaires increased their wealth by 55%, Insider's Juliana Kaplan reported. In the second half of 2020, meanwhile, 8 million Americans fell into poverty, according to a study by the University of Notre Dame and the University of Chicago.

"We're going to come out of the pandemic another degree of more unequal," Chuck Collins, director of the Program on Inequality at IPS, told Kaplan.

Oxfam suggested wealth taxes could be a good option to reverse this. In December, academics published a study of 50 years of tax cuts for the wealthy that suggested "trickle-down" economics made inequality worse and didn't lead to economic growth and employment.

Argentina became the first country to respond to the pandemic with a one-off "millionaire tax" approved by its Congress in December, which the government hopes will raise $3.78 billion to help pay for its pandemic response.

The US has also ramped up efforts to tax its highest earners.

Massachusetts Sen. Elizabeth Warren has proposed an "ultra-millionaire" tax on individual net worth above $50 million, while New York Gov. Andrew Cuomo included tax hikes for the state's richest in his 2022 budget proposal.

President Joe Biden, meanwhile, has proposed raising the corporate tax to 28% as a way to fund his $2 trillion infrastructure plan. The package, which Biden hopes will overhaul the US economy, includes investments in transportation, water, broadband, power, housing, and education.