​Sears will speed its closure of at least 50 stores

HOFFMAN ESTATES, Ill. - Following a "challenging" holiday season, Sears Holdings (SHLD) will accelerate the closure of some of its stores.

A key measure of retailing performance called comparable-store sales, which tracks sales at stores open for at least a year, dropped in the fourth quarter by 6.9 percent at Sears and by 7.2 percent at Kmart, which the also company owns.

While the quarter that contains the critical shopping season was better compared with the previous three quarters, overall same-store sales fell 9.2 percent in 2015, with Sears stores leading the decline.

Shares are down nearly 4 percent before the opening bell on Tuesday morning.

As for store closures, Sears said Tuesday it will include, but not be limited to, about 50 stores that the company recently announced it would be shuttering in the next few months.

The retailer will release its quarterly and full-year financial results on Feb. 25.