A woman shops at an Old Navy store on Black Friday in Alexandria, Virginia, Friday Nov. 28, 2014. REUTERS/James Lawler Duggan

Retailers had a merry Christmas this year, expecting to post the best holiday sales growth in three years, the Wall Street Journal reported. Sales numbers kept growing throughout the month of December, the International Council of Shopping Centers said.

Consulting firm Deloitte predicted a holiday season that would feature a 4 percent to 4.5 percent increase in sales compared to last year, and so far, early numbers seem to indicate the forecast was on track. The National Retail Federation, a trade group for the industry, expects sales will be up 4.1 percent for November and December.

Strong sales likely benefited from a confluence of positive economic indicators this year. Job growth was up, the economy in the third quarter of 2014 expanded at its fastest pace in a decade, and consumer confidence was the highest it’s been since January 2007, according to the University of Michigan consumer confidence survey. Falling gas prices likely bolstered that consumer confidence, as well.

“You can’t minimize the importance of falling gas prices and the increase in personal income,” said Jack Kleinhenz, chief economist for the NRF.

The Saturday before Christmas, known in the retail industry as Super Saturday, was especially kind to stores this year. Consulting firm Customer Growth Partners reported Super Saturday edged out Black Friday this year for the biggest sale numbers. Shoppers spent $23 billion that day versus the $20 billion spent on Black Friday.

But even after Saturday, retailers were pushing customers to spend up until the last minute. Many stores offered last-minute sales with additional discounts of 20 percent to 40 percent off, and some even extended hours to stay open all night until Christmas Day.

Not everyone expects the numbers to be as bright. Analytics firm RetailNext, which studies numbers from specialty stores and large footprint retailers, told Reuters sales were down 8.9 percent during the weekend before Christmas versus a year ago. Store traffic was also down 10.2 percent. The silver lining, however, was that shoppers who did go to the store spent more than they did in previous years.

"Even with this drop in growth, Super Saturday was still better compared to Black Friday," said Shelley Kohan, vice president of retail consulting at RetailNext. "It generated a tad more in terms of sales on slightly less traffic."

Foot traffic declines could be due in part to customers directing more of their shopping to the Web. A recent Deloitte poll found that consumers planned to spend about 40 percent of their holiday shopping budget online.