There's uncertainty over the US election, over Brexit, over interest rates, over the strength of the US economy, and over global trade.

Will the Bank of China devalue the yuan? Will the Bank of Japan aggressively target deflation? What will ECB president Mario Draghi do when he fails to hit his 2% inflation target?

Will Austria vote for an anti-immigration president? Will Italy's prime minister Matteo Renzi get the  constitutional reforms for Italy that he seeks? If not, will he resign as promised? What about the rise of euroskeptics in France and Italy?

A Financial Times survey says White House Battle Set to Chill US Economy.

"There is more uncertainty around US economic policy now than there has been for quite a while," said Lewis Alexander, economist with Nomura. "You look at what Donald Trump proposes in particular and it raises all sorts of questions, the threats around trade, the threat of the costs to move jobs overseas. It raises the degree of uncertainty . . . around investment."