Shares of Wells Fargo (WFC -5.49%) are trading roughly 5.5% lower as of 10:44 a.m. ET today after the bank reported earnings results for the second quarter of the year earlier this morning.Lowering net interest income guidanceWells Fargo reported earnings per share of $1.60 on total revenue of roughly $20.8 billion. EPS beat FactSet estimates easily, while revenue came in slightly higher than estimates. However, the stock sank after management lowered its full-year guidance for net interest income (NII), wh ...