U.S. stocks ended mostly flat on Monday as investors followed the meeting between U.S. President Donald Trump and Ukrainian President Volodymyr Zelensky and awaited Federal Reserve Chair Jerome Powell's Friday speech at the annual monetary-policy symposium in Jackson Hole,

The investing world will turn its attention to northwestern Wyoming in the week ahead, with Federal Reserve Chair Jerome Powell set to give his most important policy speech of the year on Friday at the annual Jackson Hole Economic Symposium.

What will Federal Reserve Chair Jerome Powell signal about interest rates at this year's Jackson Hole gathering? The central-bank gathering has sometimes been a venue for marking shifts in Fed policy,