NEW YORK — The Thomson Reuters Same Store Sales Index is forecasting a 0.5% gain in U.S. same-store sales for February, which represents an improvement from January but would fall short of the 3% growth some analysts consider a benchmark for a flourishing retail ­sector.

Costco Wholesale Corp. said its comparable-store sales in the four weeks through February 28 increased 4% when the negative impacts from gasoline price deflation and foreign exchange are excluded. Net sales were $8.3 billion, up 1% from a year earlier.

Rite Aid Corp. said same-store sales for the five weeks to February 27 fell by 0.8% from the previous year’s level. The drug store chain announced that February’s front-end same-store sales declined by 0.5% from a year earlier, while pharmacy same-store sales — which included a 269-basis-point negative impact from generic introductions — declined 0.9%. Rite Aid said prescription count at comparable stores increased 1.4% from the comparable period of 2015. Total drug store sales for the five-week period increased 0.1% to nearly $2.6 billion, the company said.

Prescription sales accounted for 69.4% of drug store sales at Rite Aid, and third-party prescription sales represented 98% of pharmacy sales.

Rite Aid, which has agreed to be acquired by Walgreens Boots Alliance Inc., announced that, going forward, it would no longer report sales results on a monthly basis. The company said it would continue to provide this information on a quarterly basis as part of its financial reporting. Rite Aid has been one of the few retailers still reporting monthly sales data.

At Fred’s Inc., net sales in the four weeks to February 27 increased by 12% from a year earlier. The retailer said its comparable-store sales were essentially flat compared with the prior-year period but up 0.8% from January’s level. Fred’s reported net sales of $171.1 million for February.

Fred’s credited specialty pharmacy sales for February’s sales increase. Fred’s said it posted an increase in scripts and sales in the pharmacy department despite a relatively mild cold and flu season. Health and beauty aids were also strong performers in February.