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- Walmart's 4,600 US stores are supported by a network of 42 regional distribution centers.
- Of those 42, there's "some level of automation" at 15 of them, CFO John David Rainey said.
- When a distribution center is automated, Rainey said, it sees as much as a fourfold efficiency leap.
Walmart's store fleet is staggeringly huge, and the operation to support it is similarly massive.