Walmart leads GlobalData ranking that also includes Amazon, Costco, Kroger
Regional grocer cites strong customer response to mobile checkout app
Another 700 stores to carry fresh produce by year-end, pilot of all self-checkout under way
U.S. comparable sales rise nearly 17%, atop more than 18% growth a year ago
Longtime Target executive brings diverse background at chain stores
Ahold veteran takes over with departure of Matt Lutcavage
Seasoned CFO brings deep experience from leading CPG/retail brands
Palm-scanning technology now at selected stores in four states