Here’s What We Know About the Pound’s Flash Crash: QuickTake Q&A

Investors in London woke up Friday to learn that the pound had plunged 6.1 percent against the dollar in two chaotic minutes early in the Asian day, before recovering. For a time, the world’s fourth most-traded currency resembled a frontier market -- one that has thin trading and whiplash swings -- as volatility soared and traders grasped for a reason.

The Bank of England is investigating. Analysts speculated that the initial decline may have been sparked by a “fat finger" human error, while others pointed to comments by French President Francois Hollande pushing for the European Union to negotiate hard in Brexit talks. The slide capped a tumultuous week for sterling that has seen it tumble as Prime Minister Theresa May raised the specter of a "hard Brexit" -- the U.K. losing access to the EU single market, the economic backbone of the world’s largest trading bloc.