Wall Street's biggest bank CEOs, from Jamie Dimon at JPMorgan to Brian Moynihan at Bank of America, were talking a recession as the "base case" as part of earnings reports on Friday morning. It might be a "mild" one, as Moynihan predicts, but from the world of global trade, there are several indicators backing up the bank chiefs' view of the macroeconomic landscape, flashing warning signals of continued consumer weakness for the first quarter. The flow of trade is a real-time and forward-looking indicator of consumer spending and the economy because it shows supply, demand, and consumption. Here are four...