NEW YORK (CNNMoney.com) -- After a very long and painful wait for retailers, shoppers finally came through in the last month of the year to lift crucial holiday store sales.
But monthly sales numbers Thursday from leading store chains also showed that U.S. consumers clearly shopped on their own terms, waiting much later in the season to bag the deepest discounts in stores.
Thomson Reuters, which tracks monthly same-store sales for 30 chains such as Costco, Target (TGT, Fortune 500), Gap and J.C. Penney (JCP, Fortune 500), said overall December sales for the group rose 2.9%, a far better performance than the 3.6% decline a year earlier.
The firm had initially forecast an overall sales increase of 2% for the month.
December's performance was a significant improvement from a slight 0.5% same-store sales gain in November. It was also the best monthly sales performance for the group since a 3.4% gain registered in April 2008, the firm said.
The November-December sales period is critical for the retailing industry because that two-month period can account for 50%, or more, of retailers' sales and profits for the full year.
The National Retail Federation (NRF) has forecast 2009 holiday sales to decrease 1% this year, compared to a 3.4% decline the prior year. Final sales figures for the season will be announced next week.
Given the much-improved December sales performance, industry watchers are hopeful that the final holiday sales might even show a gain.
"The numbers were very good and it's encouraging that the strength was seen across multiple retail categories," said Chris Donnelly, retail analyst with consulting firm Accenture.
"Consumers are opening up their pocketbooks more than before," he said. "They are buying more electronics and luxury items in December. Both categories are harbingers of discretionary spending."
With the economy and job concerns still on their minds, consumers still favored discounters such as Costco (COST, Fortune 500) last month. The No. 1 warehouse club operator posted a 9% gain in its same-store sales, versus analysts' expectations for a gain of 7.9%.
Same-store sales are a key measure of a retailer's performance and measure sales at stores open at least a year.
Costco's competitor BJ's Wholesale Club reported a 4.8% same-store sales increased in December.
Department store operator Sears Holding (SHLD, Fortune 500), which also owns discounter Kmart, logged a 0.4% sales gain in the month, primarily boosted by a strong 5.3% same-store gales gain in sales at Kmart. The company also raised its fourth-quarter profit estimates as a result.
"Retailers were already planning for a modest holiday sales season but consumers spent on the higher-end of expectations," said Donnelly. "This means that retailers' profits will be good."
Clothing and accessories chain Gap Inc. (GPS, Fortune 500) saw one of the biggest holiday sales rebounds last month. The company logged a 2% sales increase last month compared with a 14% drop in December sales in 2008.
And sales at Children's Place, a seller of infant and kids' apparel, rose 4% versus a 4.8% decline a year ago.
A sales rebound wasn't in store for everyone, however. Among the losers last month was teen merchandise seller Hot Topic, which suffered a 10.9% sales decline.
Limited Brands, parent of Victoria's Secret and Bath & Body Works chains, logged a disappointing 2% sales decrease. Analysts had expected a decline of 1.5%.
Department store chain J.C. Penney's sales fell 3.8% in the month.
Despite December's improvement, Donnelly said he's hesitant to say that consumer spending has turned the corner. "Consumers still face a significant headwind in the nation's high unemployment rate," he said.