January was a good month for America's retailers, judging by the latest sales reports.

Same-store sales (purchases made in outlets open at least a year) jumped 5.8% according to the International Council of Shopping Centers, which tracks 72 retail chains.

ICSC chief economist Michael Niemira, who had predicted an increase of 4% to 4.5%, attributed the surge to the improving economy, cold weather and consumers cashing in gift vouchers received over Christmas.

Significantly, January sales rose at department stores, possibly indicating an upturn in a sector that has suffered in recent months. Same-store sales were up at J C Penney (+6.4%), May Department Stores (+4.6%), Sears Roebuck (+4.6%) and budget operator Kohl's (+0.3%).

Elsewhere, Wal-Mart posted a 5.7% sales increase, ahead of its own forecasts of 3% to 5%. Target, Wal-Mart's rival in the discount sector, also came in ahead of expectations with a 5.1% rise. Gap, meanwhile, was up 3%.

Data sourced from: Financial Times; additional content by WARC staff