U.S. oil's May contract plunged into negative territory on Monday, meaning that you would have to pay to get someone to take barrels of oil off your hands. West Texas Intermediate oil trading on the New York Mercantile Exchange plunged nearly 300% to settle at negative $37.63 a barrel. The May contract expires CL.1, -5.27% CLK20 Tuesday. That one-day drop marks the first time the contract has traded negative in history and would be the largest tumle on record going back to 1983, while a finish near its current level would be far below the previous all-time low for a front-month contract, according to Dow Jones Market Data. The June contract CLM20 which is the most-active, ended down $4.60, or 18.3%, at $20.03 a barrel.