Shares in Wells Fargo fell 7.8%, shares in JP Morgan fell 1.8% and Citigroup lost 6.9% after earnings failed to beat forecasts. Banks had previously lifted solidly in the lead-up to the earnings announcements. Shares in Exxon Mobil fell 4.8% due to a regulatory probe into the oil giant. At the close, the Dow Jones index was down 177 points or 0.6%. The S&P 500 index was down 0.7% and the Nasdaq index fell by 114 points or 0.9%. Over the week the Dow fell 0.9%; with the S&P 500 and Nasdaq down 1.5%.