U.S. oil futures plunged below zero for the first time Monday, a chaotic demonstration of the dwindling capacity to store all the crude that the world’s stalled economy would otherwise be using. The price of a barrel of West Texas Intermediate crude to be delivered in May, which closed at $18.27 a barrel on Friday, ended Monday at negative $37.63. That effectively means that sellers must pay buyers to take barrels off their hands. …