Stocks eyed further gains at Monday's opening bell on this shortened trading week. The markets will close for Christmas and close early on Christmas Eve. An early holiday gift for drivers as gasoline prices in the U.S. are at a more than 5-year low. According to a Lundberg survey, the average price of regular-graded gasoline fell $0.25 in the past two weeks to $2.47 a gallon. Staples (SPLS) said 1.16 million payment credits could have been compromised. The retailer announced earlier, they were investigating a hack attack happened at its stores from July to September. Walgreen (WAG) is planning to withdraw its stock listing on the New York Stock Exchange and the Chicago Stock Exchange once its merger with Alliance Boots is completed. The combined company will list on the Nasdaq under the ticker symbol 'WBA.'