A new report from the charity also found that the wealth of billionaires has grown six times faster than that of ordinary workers since 2010, with another billionaire minted every two days between March 2016 and March 2017.
Oxfam used its findings to paint a picture of a global economy in which the wealthy few amass ever-greater fortunes while hundreds of millions of people are "struggling to survive on poverty pay".
"The billionaire boom is not a sign of a thriving economy but a symptom of a failing economic system," Oxfam executive director Winnie Byanyima said in a statement.
Oxfam also emphasised the plight of women workers, who "consistently earn less than men" and often have the lowest paid, least secure jobs. Nine out of 10 billionaires are men, it added.
The report, titled "Reward Work, Not Wealth", used data from Credit Suisse to compare the returns of top executives and shareholders to that of ordinary workers.
It found that chief executives of the top five global fashion brands made in just four days what garment workers in Bangladesh earn over a lifetime.
To fight rising inequality, Oxfam called on governments to limit the returns of shareholders and top executives, close the gender pay gap, crackdown on tax avoidance and increase spending on healthcare and education.
The study was released on the eve of top political and business figures meeting at a luxury Swiss ski resort for the annual World Economic Forum, which this year says it will focus on how to create "a shared future in a fractured world".
"It's hard to find a political or business leader who doesn't say they are worried about inequality," said Byanyima.
"It's even harder to find one who is doing something about it. Many are actively making things worse by slashing taxes and scrapping labour rights."
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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