Sector deals have slipped to their lowest ebb since Q1 2019, but what’s to blame? Alex Wilhelm 9 hours Walmart reported earnings this morning. Most of the numbers are immaterial to you and I, having little to nothing to do with the world of private capital and startups, but one metric did leap out: In its quarter ending July 31, Walmart’s U.S. “e-commerce sales” grew by 97% compared to the year-ago quarter, with what the company called “strong results across all channels.” The Exchange explores startups, markets and money. You…