Costco (COST 0.34%) stock has raced back into Wall Street's good graces in the final weeks of 2021. Share prices are up 47.6%, roughly double the broader market's 24.8% spike so far this year and well above main rival Walmart's (WMT 1.00%) flat performance this year.

That performance gap implies that investors are expecting big things from the world's second-largest retailer. So let's look at three of the major trends to watch for from Costco in 2022.

Person shopping in a warehouse.

Image source: Getty Images.

1. More sales growth to come for Costco

If Costco proved one thing during the pandemic, it's that shoppers enjoy visiting its warehouse stores, whether they're looking for essentials like tissue paper or luxuries such as consumer electronics. Sales rose 14% in the full year that ended in late August after jumping a year earlier, and there's likely more growth to come.

Shopper traffic through late November was up a blistering 6% in the core U.S. market, management said in its first-quarter 2022 earnings call in December. And average spending was up 9% to help push comparable-store sales up 10% after adjusting for gas price swings. Each of those figures beat Walmart and confirm that Costco is still in a league of its own when it comes to sales growth.

2. Costco has a growing subscriber base

Costco has all the trappings of a retailer, but its real business is selling memberships to its warehouses. And that business is booming. Just below 92% of shoppers renewed their memberships over the last year. That renewal rate is up 0.3 percentage points in just three months and near an all-time high.

Costco is seeing more members sign up for auto-renewals and is benefiting from a shift toward its more premium executive subscription. Those trends all point to significant membership gains in 2022.

That's great news for investors since Costco generates more than half of its earnings from membership fees. An expanding base of engaged shoppers is the surest path for the business to continue seeing market-beating profit growth.

3. Higher membership fees and dividends may be coming

Costco is famously careful about raising prices for merchandise even in inflationary times like these. One of its most valuable competitive assets is its price leadership position in the industry. Customers count on receiving the best possible price on most products, which allows them to shop freely without worrying about whether they're getting enough value.

However, Wall Street is more focused on the price of membership fees, since a boost there translates directly into higher earnings over the next few years. Costco tends to hike that fee every five or six years, and mid-2022 will mark five years since its last increase -- the one that pushed its standard membership fee up to $60 per year. It's possible that shoppers will see another increase announced by late 2022.

Investors might be in for another treat in 2022 that more directly impacts their portfolios. Costco has made a habit of returning excess cash to shareholders through special dividends, including one in late 2020, and its growing resources make another such payout likely over the next year.

"We, and the shareholders seem to like when we do it," CFO Richard Galanti said in early December when asked about another big payment over the next few quarters. No decision has been made yet, but dividends are likely to rise in 2022, adding another lift to shareholders' returns.