US retailer Spartan Stores posted a 21.6% jump in net earnings for the second quarter as a result of stronger sales.

For the 12 weeks to 13 September, net earnings reached US$11.1m from US$9.1m in the same period last year.

Net sales rose 4.8% to US$626.8m from US$598.1m in last year's second quarter, helped by incremental fuel sales, strong store sales growth and higher distribution sales.

Second-quarter operating earnings increased 16.9% to reach US$22.5m compared with US$19.3m for the comparable period in 2007. The improvement, the Michigan-based company said, was down to "improved distribution margins, retail store efficiency improvements, and the expiration of the Michigan Single Business Tax (SBT)".

"We are pleased to be achieving steady progress strengthening our market position as we confront challenging economic conditions," said CEO Dennis Eidson. "As anticipated, comparable-store sales for the quarter improved due to more seasonal northern Michigan weather conditions and enhanced sales growth."

Eidson said he expects comparable retail store sales to increase in the "low single digits" during the second half of fiscal 2009 due to the cycling of remodelled and relocated stores and absence of Easter holiday sales in this year's fourth quarter.

Earlier this week, Spartan purchased 17 retail grocery stores, including 15 pharmacies, from VG's Food Center and VG's Pharmacy, a privately-held Michigan-based retail grocery operator and currently the company's largest distribution customer.

The company said it expects the transaction to close near the end of its fiscal 2009 third quarter.