Foot Locker (NYSE: FL) investors have been enduring significant volatility in 2018 as the company posts declining sales and falling profit margins. Yet the shoe retailer's last few quarterly reports contained encouraging signs that this slump is only temporary. The company took some tough steps toward improving its inventory position while promising that the price cuts will eventually stabilize and pave the way for stronger earnings.Those moves paid off in the quarter that just closed, and the company returned to modest sales growth at its existing locations.