John Petrides, portfolio manager at Tocqueville Asset Management, breaks down the factors that led to narrowing margins for the banking giant JP Morgan Chase and the concerns for an overall economic slowdown. "The miss was really driven by an accounting feature called CECIL, current expected credit losses, which is something that was rolled out a couple of years ago and is now in full play," he said. "Basically what that means is every loan a bank makes, now they have to assign some probability of a loss to the loan at the moment that they issued a loan."