There’s trouble coming as the chasm between the richest of the rich and everyone else continues to widen. So says a report prepared by the World Economic Forum, the nonprofit foundation that hosts its annual conference of business leaders in Davos, Switzerland, popular with the world’s billionaires.

The forum’s 14th annual assessment of risks, issued just ahead of the Davos gathering, makes clear that social instability, whether measured in mere riots or in bloody revolutions, is the likely outcome of increasing inequality.

The report speaks of a lost generation of young people worldwide who are finishing school only to find a paucity of jobs, which in turn creates pressure to lower wages.

“Widening gaps between the richest and poorest citizens threaten social and political stability as well as economic development,” the report said.

Three of the report sponsors are specialists in pricing risk, the American insurance broker and risk advisory firm Marsh & McLennan and the European insurers Swiss Re and Zurich Insurance Group.

The four-day Davos conference, which begins today, will draw six dozen or so billionaires this year as well as several hundred other people rich enough to have their own jets. Davos will also draw a far larger crowd of government officials, vendors of financial services and journalists.

That those at the apex of the global economy brought forth this report should end the debate over whether inequality poses a problem, but it won’t.

To those who deny inequality is a problem, or herald inequality as an economic good, the report can be dismissed as simply the claims of an interest group. And why trust what billionaires say any more than what a minority of economists, sociologists and writers (including me) has been pointing out for two decades?

Oxfam, the British relief charity, keyed off the Davos report with one of its own that made two powerful points:

The 85 richest humans hold more wealth than the 3.5 billion people who constitute the bottom half.

These disparities in wealth and income result from “political capture,” in which the wealthy use their economic power to make sure “the rules bend to favor the rich, often to the detriment of everyone else. The consequences include the erosion of democratic governance, the pulling apart of social cohesion, and the vanishing of equal opportunities for all.”

Here is a stark indicator of just what happens when the rules are bent to favor the rich, as I have been documenting for many years.

Adjusted for inflation, Americans reported $1.1 trillion more income in 2012 than in 2009, when the Great Recession officially ended midyear. That’s a 15 percent real increase.

Where did that increase go? America’s 16,000 top-earning households enjoyed nearly a third of it. The top 1 percent captured 95 percent of the nation’s income growth. The top 10 percent of Americans, the best-off 31 million people, enjoyed all the national income growth.

As for the vast majority of Americans, the bottom 90 percent, they were worse off in 2012 than during the Great Recession. Even though the economy improved in those years, their wallets shrank until they were 15.7 percent thinner, IRS data analyzed by economists Emmanuel Saez and Thomas Piketty showed.

Indeed, the vast majority’s average 2012 income fell back to the level of 1966.