This article first appeared on GuruFocus.

Costco Wholesale (NASDAQ:COST), a membership-based warehouse retailer, delivered another month of blockbuster sales, yet the stock still slipped about 0.3% during Friday's regular session. July net sales climbed 10.7% year over year to $23.12 billion from $20.89 billion, proving shoppers continue to pack Costco's warehouses even as consumer spending remains under pressure. The reporting period ended Aug. 2.

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Costco Stock Slips Despite 10.7% July Sales Jump  · us.finance.gurufocus
Costco Stock Slips Despite 10.7% July Sales Jump · us.finance.gurufocus

The GF Value chart also tells an interesting story. With the shares trading roughly 8.2% below GuruFocus' estimated GF Value of $1,030, the recent pullback has taken some of the heat out of the valuation and could leave long-term investors looking at the stock a little differently.

The momentum wasn't limited to one month. During the first 48 weeks of Costco's fiscal year, net sales surged 10.1% to $273.55 billion from $248.35 billion a year earlier, with July actually growing faster than the year-to-date average. That's an impressive feat for a retailer already generating well over a quarter-trillion dollars in annual sales. The update didn't include margins or earnings, but it once again showed Costco's traffic, pricing power and membership model continue firing on all cylinders.

So why did the stock barely move? Because investors expect nothing less. Costco has built a reputation for delivering elite execution, and another double-digit sales report simply reinforces what the market already knows. The next earnings release will matter far more, revealing whether those booming sales are flowing through to margins, profits and free cash flow. If they do, the recent dip could end up looking more like an opportunity than a warning sign.