Stocks dropped for a second straight week last week, as both the Dow Jones Industrial Average (^DJI 0.67%) and the S&P 500 (^GSPC -0.31%) shed less than 1%. The decline still left investors looking at significant gains so far in 2021, with the Dow up 13% and the S&P 500 up 18%.

Earnings season continues with fresh earnings reports from several retailers over the next few trading days. Let's take a closer look at some highly anticipated announcements from this list, by Costco (COST -0.02%), Nike (NKE -0.01%), and Stitch Fix (SFIX -2.55%).

A man shopping in a bulk retailing store.

Image source: Getty Images.

Costco's renewal rate

Thanks to its monthly sales updates, investors already know that Costco had a great fiscal fourth quarter. Comparable-store sales jumped 9% in August, the warehouse giant reported in early September, which telegraphs good news in the upcoming earnings report on Thursday.

That announcement will add context around it fiscal 2021 performance, including an update on its profitability, which has been edging higher lately. But the big number to watch this week is Costco's renewal rate. Roughly 91% of its members have been renewing their subscriptions lately, reflecting solid engagement and industry-leading customer satisfaction.

Those wins support sales growth over time, but they also lay the foundation for rising membership fees. Costco hasn't raised its subscription prices in a few years, and Wall Street is hopeful that the next boost might come in fiscal 2022.

Nike's inventory

Rival Lululemon Athletica recently set the stage for what could be a strong earnings report out of Nike on Thursday. The athleisure specialist said it was enjoying accelerating sales growth and booming earnings as customers flocked toward innovative new product releases in the early summer.

Nike had a busy quarter for product launches, too, which is one reason most investors are looking for sales to rise in the low double-digit range this fiscal year, to roughly $50 billion, following last year's 19% spike.

Wall Street is even more excited about management's prediction of a new financial model that's more profitable thanks to direct-to-consumer sales. But the next portion of that race involves having Nike successfully raise prices to offset higher costs. Look for executives to discuss any supply chain challenges that might affect the holiday shopping season this week, too.

Stitch Fix's shipping update

It has been a wild ride for Stitch Fix shareholders this past year, and that volatility is likely to continue around its Tuesday earnings release.

On the downside, the apparel specialist might have been hit by a clogged supply chain and spiking transportation costs. Several industry peers have noted these challenges, and Stitch Fix's delivery model makes it more sensitive to shipping bottlenecks than its rivals are. Yet the business showed impressive resilience in the previous quarterly outing as CEO Elizabeth Spaulding took over for founder Katrina Lake.

Spaulding should spent some time highlighting Stitch Fix's new direct-buy offering that gives it a chance to play in a much bigger retailing space. That service went live nationally in August and has the potential to accelerate sales growth. But its more immediate concern is keeping inventory flowing smoothly through its system, at affordable prices, through a holiday shopping period that's likely to stress the freight delivery network over the next few months.