NEW YORK: Forever 21, Burberry and Zara are some of the brand owners making the most effective use of Facebook to engage consumers, according to research from Booz & Co.

The consultancy assessed the number of "likes" several leading companies had achieved compared with their overall revenues, serving as a "proxy for the way people feel about ... products and services."

Forever 21, the clothing retailer, led the rankings, having gained over 5,000 followers on Facebook for every $1m it earned in sales, a figure standing at 4,000 for Burberry, the luxury label.

"The absolute stars of the chart were midsized apparel brands such as Forever 21 that cater to (Facebook-crazy) teenage girls," the study said.

Starbucks, the coffee house chain, posted a score of almost 2,500 here, ahead of Levi's, the jeanswear manufacturer, on just over 2,000, and Gucci, the luxury line, falling slightly below this benchmark.

Coca-Cola, the soft drinks group, Yahoo, the online operator, and Zara, the fast-fashion retail chain, all registered totals of around 1,000 on the same terms, Booz & Co revealed.

Elsewhere, the consultancy matched its own "likes-per-million" data with the annual brand valuations conducted by Interbrand, creating an index that determines relative performance on this metric.

Burberry, Yahoo and Zara all "over-indexed" on this measure, alongside McDonald's and Pizza Hut, the fast-food specialists, BlackBerry, the telco, Adidas, the sportswear giant, and Heineken, the beer.

Another confirmatory finding from the study was that being a very large, well-known business did not automatically equate to social success, as shown by the fact Wal-Mart had 10.6m fans, versus over $400bn in revenue.

This translated to less than 25 "likes" per million dollars in sales, an amount well behind much smaller chains such as Macy's and Kohl's, the department store groups.

Based on its sample, Booz & Company argued the average "best in class" total received roughly 2,000 likes per million dollars in revenue, not including the fans effectively "bought" using contests and coupons.

A greater degree of complexity results where firms possess a range of assets, and thus boasted an official corporate presence on social media as well as individual brand pages, it added.

For example, some 770,000 people had "liked" Kraft on Facebook, whereas 23m had liked Oreo, the organisation's cookie brand, meaning more in-depth analysis could be beneficial.

Data sourced from Booz & Co; additional content by Warc staff