Natural gas producers are finally realizing that the age-old adage is true: If you find yourself in a hole, stop digging. Explorers have idled drilling equipment at historic rates — a drop in prices has resulted in the fewest rigs in at least three decades searching for new output. Southwestern Energy Co., the third-largest U.S. gas producer, has stopped drilling altogether, while Chesapeake Energy Corp. has no rigs in the gas-rich U.S. East, down from an average of about 13 in 2014. It’s part of a broader cost-cutting effort as companies aim to weather the downswing, betting that a price recovery will begin this year. While some unfinished wells can be used to keep up output, the industry is facing a sharp drop in future production without new drilling investment. The lack of exploration is particularly troublesome given that output from gas wells tends to decline sharply from initial […]