Dallas Fed President Rob Kaplan, a nonvoting member of the Fed's committee, said in another speech the case for a rate hike has strengthened in the past few months. Also, Fed Governor Lael Brainard unexpectedly announced she'd deliver a speech Monday.
Investors have been closely listening to Fed officials and looking at economic data, trying to gauge when the Fed might raise rates. Market expectations for a rate hike this month were 24 percent on Friday, up from 18 percent Thursday, according to the CME Group's FedWatch tool.
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