Their online growth rate went down so much in the most recent quarter, because they rolled year over year past the acqisition of Jet.com. It's an issue of YoY comparables.

"Walmart's e-commerce sales growth in its U.S. business slowed to 23 percent during the fourth quarter, a sharp decline from 50 percent in the third quarter. It noted last year's results got a big boost from its acquisition of online retailer Jet.com."

http://www.chicagotribune.com/business/ct-biz-walmart-earnin...