Sen. Bernie Sanders on Monday unveiled a proposal to reduce massive disparities between executive and worker pay by hiking taxes on corporations that pay their CEOs dramatically more than median employees.

"The American people are sick and tired of corporate CEOs who now make 300 times more than their average employees, while they give themselves huge bonuses and cut back on the healthcare and pension benefits of their employees," Sanders, a 2020 Democratic presidential candidate, said in a statement.

Sanders's plan would impose a tax increase of 0.5 percent on corporations that pay their CEOs between 50 and 100 times more than their median employees. The penalty would increase progressively for companies with larger CEO-worker pay gaps.

The senator's website outlines the tax penalties under the "Income Inequality Tax Plan," which would apply to private and public corporations with annual revenues of more than $100 million.

Companies that pay CEOs between 50 and 100 times more than their median employees: +0.5 percent

Between 100 and 200 times: +1 percent

Between 200 and 300 times: +2 percent

Between 300 and 400 times: +3 percent

Between 400 and 500 times: +4 percent

More than 500 times: +5 percent

If the plan were in effect last year, according to the senator's office, Walmart would have paid as much as $790 million more in taxes, McDonald's as much as $110.9 million more, and JPMorgan Chase as much as $991.6 million more.

"At a time of massive income and wealth inequality, the American people are demanding that large, profitable corporations pay their fair share of taxes," said Sanders. "It is time to send a message to corporate America: If you do not end your greed and corruption, we will end it for you."

The Sanders campaign said the revenue raised by the plan would be used to finance the senator's proposal to eliminate all $81 billion of medical debt in the United States.

Americans are sick and tired of corporate CEOs making hundreds of times what their workers make. Walmart: 1,076 to 1

The Home Depot: 486 to 1

Nike: 379 to 1 We say to corporate America: If you don't end your greed and corruption, we will end it for you. https://t.co/0fW4y4rALS — Bernie Sanders (@BernieSanders) September 30, 2019

The plan comes as a new report released Monday by the Institute for Policy Studies (IPS) detailed the "staggering" CEO-worker pay gaps at some of America's largest and most profitable corporations. It also comes just days after the Census Bureau found that U.S. inequality in 2018 reached its highest level in five decades.

"At the 50 publicly traded U.S. corporations with the widest pay gaps in 2018, the typical employee would have to work at least 1,000 years to earn what their CEO made in just one," IPS found. "Among S&P 500 firms, nearly 80 percent paid their CEO more than 100 times their median worker pay in 2018, and nearly 10 percent had median pay below the poverty line for a family of four."

Sarah Anderson, project director at IPS and lead author of the new report, said in a statement that a tax penalty of the kind proposed by Sanders would "build on the living wage movement by encouraging corporations to lift up the bottom and bring down the top of their wage scales."

"Such reforms would also give a boost to small businesses and employee-owned firms and cooperatives that spread their resources more equitably than most large corporate enterprises," said Anderson.