Shares in discount retailer 99 Cents Only Stores closed up nearly 6 percent and continued to gain in after market trading Monday after the company reported a rise in third quarter profit due to increased margins.

For the quarter ended Dec. 31, the company reported income of $9.5 million (14 cents per share), compared with $8.9 million (13 cents) from the same period a year earlier. Analysts polled by Thomson Financial anticipated earnings of 11 cents per share.

Sales for the City of Commerce-based retailer also increased 8 percent to $325 million, slightly missing Wall Street’s expectations of $328 million.

Same-store sales for the quarter increased 2.9 percent and the company added that results were boosted by a new pricing structure that has allowed it to increase gross margins on certain items.

Shares closed up 5.5 percent and continued to gain another 6.7 percent to $9.26 in after-market trading Monday on the New York Stock Exchange.