Sales and profits rose at Family Dollar during its fourth quarter, the retailer reported Wednesday, as the company continued opening new stores and customers spent more on each visit.

Family Dollar’s quarterly sales rose 10.8 percent compared with the same quarter a year ago, to $2.36 billion. The company said both a higher number of customers and a higher average transaction helped boost that number. Sales at stores open a year or more, considered a key measure of a retailer’s health, rose 5.4 percent.

The company’s profit was up, but not as much as analysts hoped. Family Dollar earned 69 cents per diluted share, compared with 66 cents per diluted share in the same quarter last year. Analysts had forecast 75 cents per share. Actual profit edged up 1.4 percent, to $80.9 million, compared with $79.8 million in the same quarter last year.

A class-action lawsuit settlement ate up much of the difference. Family Dollar incurred an $11.5 million charge in the fourth quarter, to settle a suit by more than 1,700 New York store managers alleging that they were illegally denied overtime. Excluding that charge, Family Dollar’s profit would have risen 10.3 percent, and the retailer would have hit the 75-cent-per-share analyst estimate for profit.

The year was a major time of growth for Family Dollar, which renovated more than 800 stores and opened 475 new stores, including 41 in California, a new market for Family Dollar. The retailer now operates 7,442 stores.

“I can’t remember a time in our company’s 53-year history when we accomplished so much, so quickly,” said CEO Howard Levine, during a conference call with analysts.

“We were laser-focused on becoming more relevant to our customers and driving more trips to our stores,” said Family Dollar president Mike Bloom. To that end, the retailer added 600 health and beauty items, Pepsi products, 400 new food items, and more impulse items such as candy and magazines to its stores. Family Dollar also started selling tobacco products, which 6,000 of its stores now carry.

For the full year, Family Dollar’s sales rose 9.2 percent, to $9.3 billion. Profits were up 8.7 percent, to $422 million.

Discount stores are continuing a strong run, as people continue to look for ways to cut back. Goodlettsville, Tenn.-based Dollar General, Family Dollar’s largest rival, posted profits of $214 million for its most recent quarter, up 47 percent from the same quarter a year ago.

While Family Dollar remains focused on its core customer, who makes $40,000 or less, executives said renovations to stores and the expanded assortment of consumable items could lure more “trade-down” shoppers making up to $70,000.

Gross profit margins, an area of concern for investors, remained under pressure, as Family Dollar continued to increase its sales of low-margin consumable goods, such as food. For the full year, gross profit margins fell to 34.9 percent of sales, down from 35.5 percent of sales last year. The company is investing in its private brands, price management systems, and increased sourcing from China to counter the trend. Family Dollar’s net profit margin remained virtually unchanged, at 4.5 percent.

Family Dollar is opening an office in Shanghai, its third in Asia, and hopes to import 13 percent of its goods directly from Asian factories by 2015.

To support the increased growth during the year, Family Dollar spent far more on capital expenditures, such as store openings and remodels. The company spent $603 million in capital expenditures, compared with $345 million in fiscal 2011. Family Dollar said it expects to spend up to $650 million on capital expenditures in fiscal 2013, as it opens 500 new stores.

Family Dollar’s stock closed up $2.56, nearly 4 percent, at $68.56 a share.