St. Louis Fed President James Bullard speaks about the U.S. economy during an interview in New York. REUTERS/Lucas Jackson

(FILES) This file photo taken on August 9, 2011 shows the US Federal Reserve building in Washington, DC. US Federal Reserve policy makers last month believed risks to the US economy had lessened but wanted to keep their interest rate policy "options open", according to minutes released August 17, 2016. / AFP PHOTO / KAREN BLEIERKAREN BLEIER/AFP/Getty Images

Pedestrians throng the busy Oxford street in central London on August 17, 2016. From computers and cars to carpets and food, Britain's decision to leave the EU is beginning to hit consumers in the pocket, having already spread uncertainty through the property market. The consequences of the shock vote have so far been mainly theoretical, but recent data suggest that the country's tumbling currency is about to reach the High Street. The Office for National Statistics publishes retail sales figures for July on August 18, 2016. / AFP PHOTO / DANIEL LEAL-OLIVASDANIEL LEAL-OLIVAS/AFP/Getty Images

Pedestrians throng the busy Oxford street in central London on August 17, 2016. From computers and cars to carpets and food, Britain's decision to leave the EU is beginning to hit consumers in the pocket, having already spread uncertainty through the property market. The consequences of the shock vote have so far been mainly theoretical, but recent data suggest that the country's tumbling currency is about to reach the High Street. The Office for National Statistics publishes retail sales figures for July on August 18, 2016. / AFP PHOTO / DANIEL LEAL-OLIVASDANIEL LEAL-OLIVAS/AFP/Getty Images

GLENRIDDING, ENGLAND - AUGUST 17: Sail boats on Ullswater enjoy the fine weather on August 17, 2016 in Glenridding, England. The Lake District continues to recover after the devastating Storm Desmond hit the region in December last year. Many bridges and roads have been fully repaired but some homes and businesses are still being rebuilt. The recent fine weather has seen tousrists flock to see the natural beauty of the hills and dales. The Lake district is Britains most visited national park with tourists arriving from around the world for its lakes, valleys, woodlands and fells. (Photo by Christopher Furlong/Getty Images)

GLENRIDDING, ENGLAND - AUGUST 17: Sail boats on Ullswater enjoy the fine weather on August 17, 2016 in Glenridding, England. The Lake District continues to recover after the devastating Storm Desmond hit the region in December last year. Many bridges and roads have been fully repaired but some homes and businesses are still being rebuilt. The recent fine weather has seen tousrists flock to see the natural beauty of the hills and dales. The Lake district is Britains most visited national park with tourists arriving from around the world for its lakes, valleys, woodlands and fells. (Photo by Christopher Furlong/Getty Images)

KESWICK, ENGLAND - AUGUST 17: People queue for a pleasure boat ride on Derwent Water on August 17, 2016 in Keswick, England. The Lake District continues to recover after the devastating Storm Desmond hit the region in December last year. Many bridges and roads have been fully repaired but some homes and businesses are still being rebuilt. The recent fine weather has seen tousrists flock to see the natural beauty of the hills and dales. The Lake district is Britains most visited national park with tourists arriving from around the world for its lakes, valleys, woodlands and fells. (Photo by Christopher Furlong/Getty Images)

KESWICK, ENGLAND - AUGUST 17: People enjoy a paddle to cool off in Derwent Water on August 17, 2016 in Keswick, England. The Lake District continues to recover after the devastating Storm Desmond hit the region in December last year. Many bridges and roads have been fully repaired but some homes and businesses are still being rebuilt. The recent fine weather has seen tousrists flock to see the natural beauty of the hills and dales. The Lake district is Britains most visited national park with tourists arriving from around the world for its lakes, valleys, woodlands and fells. (Photo by Christopher Furlong/Getty Images)