Forward-thinking hedge funds and Wall Street analysts are only beginning to apply Facebook Inc. (NASDAQ:FB) metrics to forecast companies’ growth.

But, even though the more than 33 million fans of Wal-Mart Stores, Inc. (NYSE:WMT) may have an immediate effect on the sales, long-term customer loyalty can improve the outlook for the country’s largest retailers.

“One thing people note in terms of social media, but particularly Facebook, is that it’s better used post-purchase,” Len Cercone, partner at the Boston-based integrated marketing agency CerconeBrownCompany, told International Business Times. “It’s about fans and people that love you.”

And millions have expressed that love with the click of a “like” button. Behind Wal-Mart was Victoria’s Secret (NYSE:LTD), Target Corporation (NYSE:TGT), adidas AG (ETR:ADS) and Amazon.com, Inc. (NASDAQ:AMZN), with between 18 million and 22 million followers.

But the breadth of brands on Citi’s list – including big-box store Kohl’s Corporation (NYSE:KSS), Macy’s, Inc. (NYSE:M) and the ailing electronics giant Best Buy Co., Inc. (NYSE:BBY) – indicates the fast-aging demographic on the social network.

“Younger people are flocking to things like Instagram and Vine,” Brittany Leaning, social media manager at the Cambridge-based digital marketing firm Hubspot, told IBTimes. “Older folks are coming to Facebook and younger folks are leaving.”

That leaves one group of outliers: The so-called 3As of teen fashion – Aeropostale Inc. (NYSE:ARO), American Eagle Outfitters (NYSE:AEO) and Abercrombie & Fitch Co. (NYSE:ANF) – were growing on Facebook, despite declining sales and popularity among their targeted teenaged buyers.

The brands, facing weak quarters this year, likely purchased sponsored posts on Facebook, suggesting to algorithmically likely users that they fan their pages, a marketing insider told IBTimes. But Facebook does not release its brand analytics to anyone but the owner of that brand.

“I would not use Facebook as a hard metric,” Cercone said. “I would use it as a bellwether of the likelihood of consumers being loyal to your brand.”

Here are the top 25 retail brands growing on Facebook:

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The top 25 key retailers on Facebook, and how they are growing. Citi