Did Prime Day Sink July Retail Numbers? by David Z. Morris @FortuneMagazine August 13, 2016, 4:44 PM EDT E-mail Tweet Facebook Linkedin Share icons U.S. retail results for July were announced yesterday, with flat month-over-month growth that fell short of projections of around 0.4%. That was an especially big surprise after an overall 4.2% acceleration in retail sales through the second quarter of the year. Conventional wisdom has that slowdown signaling a tapering of consumer demand, and broader economic cooling. But what if the real culprit was . . . Amazon’s Prime Day sale? Get Data Sheet, Fortune’s technology newsletter. Patti Domm at CNBC lays out the case. Most fundamentally, non-store sales (mostly online sales) beat the trend, surging 1.28% month-over-month. According to retail analyst Paul Hickey, this represents a “Prime bounce,” and Amazon [fortune-stck symbol=”AMZN”] reported that the July 12th sale was its biggest day ever. But wait, there’s more! The brick-and-mortar categories that suffered most in July were apparel, electronics, and general merchandise, categories where Amazon is an attractive option. By contrast, in-store sales of furniture, autos, and health products—where Amazon holds less sway—actually did okay, ticking up between .13% (Health) and 1.13% (Autos and Parts). Another analyst, Diane Swonk, suggests to CNBC that this points to increased discounting by brick-and-mortar stores hoping to fight back against Prime Day hype. Instead of signaling a sudden dropoff in consumer enthusiasm, Swonk says the July results just mean consumers “got good discounts.” For more on Amazon, watch our video. It’s a compelling theory, but there is some counter-evidence. For example, restaurant and bar spending, which Amazon shouldn’t have much influence over either way, also fell in July. And sporting goods and hobby stores, which would seem only partly subject to any Prime effect, tanked by a whopping 2.2%. What both of those have in common is that they’re discretionary—the first type of spending to go overboard when consumers sense rough waters ahead.