America's largest discount retailer Wal-Mart Stores Inc. reported a 21 percent drop in net profits in its fourth quarter Thursday and gave a subdued forecast for the current year. Quarterly earnings fell to 4.4 billion dollars compared to the 5.6 billion dollars a year ago, according to the financial results released by the retail giant, headquartered in Bentonville, Arkansas, on its official website. Earnings per share were 1.34 dollars, down 19.8 percent from the 1.67 dollars a year before, the statement said. Sales were chipped away by a number of factors, including severe winter weather and slow spending during the holiday sales season, cuts to food stamps and growing competition. The results were also affected by write-offs in its foreign operations, including non-income tax contingencies in Brazil and the closure of under-performing stores in China and Brazil. Doug McMillon, who took over as Wal-Mart's CEO on Feb. 1, said in the statement the company would invest "aggressively" in e-commerce and increase small store roll-out in the United States to improve its performance. "The combination of super-centers and smaller formats closer to customers' homes, along with e-commerce and mobile commerce, will enable us to increase our relevance for the Wal-mart brand around the world," McMillon said.