Traders are bidding down Costco Wholesale's (NASDAQ:COST) share prices this morning, a trend that began yesterday before market close, despite positive sales figures in the company's fiscal first-quarter 2021 earnings report. The retailer and warehouse club operator's comparable sales and other metrics still rose year over year, but didn't grow as strongly as in the previous quarter, prompting the current minor stock market retreat.

The quarter, which saw net sales grow 16.9% compared to 2019, ended on Nov. 22, while the retail month of November's net sales rose 15.1% year over year. Wall Street consensus expected comparable sales or comps to grow by 13.8% for the month, whereas actual comp growth was slightly lower at 13.4%. With comps growing 15.4% for the quarter as a whole, Costco's sales do appear to be decelerating slightly as early winter arrives.

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E-commerce growth remained predictably strong, climbing 86.4% for the quarter. The rise in internet sales was 71.3% for November itself, once again showing a pattern of deceleration at year-end.

The slight pullback appears to simply be part of the natural stock market cycle, since Costco's sales figures remain strong and its stock is still trading at highest-ever levels. With its competitive pricing and membership model, the company remains one of the most effective operators in today's market conditions, proving its ability to prosper through the disruptions of the COVID-19 pandemic and other 2020 events.

The company has continued paying its quarterly dividend and additionally turned its cash windfall from climbing sales into a $10 special dividend, which it announced in mid-November.