Australia’s two richest people, Gina Rinehart and Harry Triguboff, own more than the poorest 20% of the country’s population, research has found.

Worth an estimated combined $21.5bn ($US16.1bn), the nation’s richest woman and the Meriton property boss are among the wealthiest 1% of Australians, who together own more than the bottom 70%, the report from Oxfam found.

The statistics, published in a global report, An Economy for the 99%, come as the world’s political and business leaders gathered for the annual World Economic Forum in Switzerland.

The residential property developer Harry Triguboff. Photograph: Dan Himbrechts/AAP

Oxfam Australia’s chief executive, Dr Helen Szoke, said the margin between the nation’s rich and poor mirrored a worldwide trend.

“The scale of the global wealth inequality crisis is much, much greater than we had feared,” Szoke said on Monday.

Globally, the richest eight people – including the founder of Microsoft, Bill Gates, and Facebook’s Mark Zuckerberg – own as much as the poorest half of the world’s population, or about 3.6bn people.

“Collectively, the world’s richest eight men have a net wealth of $US426bn [$A568bn],” Szoke said. “Such an extreme divide between the rich and the rest risks plunging future generations into political instability, undermining our democratic institutions and creating economic upheaval.”

Despite the world’s wealthiest often being the most generous, Szoke said, having so much wealth in the hands of just eight people “highlights how broken our economic system really is”.

She called for the federal government to introduce tougher laws that force large Australia-based multinational companies to publicly report incomes, employees, profits earned and taxes paid in every country of operation.

Szoke said ending the “extreme concentration of wealth” in Australia was particularly important given the Centrelink debt recovery crackdown affecting some of the most vulnerable people in the country.

Oxfam’s analysis is based on new Credit Suisse data, which reveals that the bottom half of the world’s population is significantly worse off than previously thought, with far more debt and fewer assets.

The research shows the people in the poorest half of the Australian population have little or no combined net wealth, with about 6% of national wealth between them. The richest 10% had more income growth – more than 28% – than the poorest half of Australians combined.

Szoke said the federal government needed to introduce tougher laws that forced large multinationals based in Australia to publicly report incomes, employees, profits earned and taxes paid for every country in which they operate.

Previous research by Oxfam estimates that tax dodging by Australian-based multinationals is costing nearly $6bn a year in tax revenue in Australia and depriving developing countries of nearly $3bn annually.

World’s richest people

• Bill Gates $US75bn



• Amancio Ortega $US67bn



• Warren Buffett $US60.8bn



• Carlos Slim Helu $US50bn



• Jeff Bezos $US45.2bn



• Mark Zuckerberg $US44.6bn



• Larry Ellison $US43.6bn



• Michael Bloomberg $US40bn





Australia’s richest

• Gina Rinehart $US8.8bn



• Harry Triguboff $US7.3bn