Macy's (M) stock jumped 8% in premarket trading after the department store chain reported better-than-expected fourth quarter earnings results as it heads into the third year of its turnaround strategy. CEO Tony Spring told Yahoo Finance that it continues to see signs of a K-shaped economy, or the growing divide between high earners and low-income households. "The lower-income consumer is pressured," Spring said. "The middle-income consumer is being choiceful and trying to find opportunities to buy. .. ...