NEW YORK: Coming as many US retailers report better-than-expected sales for August, a new study has identified the top ten fastest-growing retailers and suggests that discounting, e-commerce and adding more stores are the reasons for success.

The research from investment analysts 24/7 Wall St listed Apple Stores/iTunes as the retail chain with the highest sales growth between 2011 and 2012, according to USA Today.

It achieved 34.6% sales growth, taking its US sales to $24bn in 2012, a rate of growth more than double the 16.8% recorded by AT&T Wireless, the telecoms group, which was ranked second.

Basing its findings on data from STORES Media, the publishing arm of the National Retail Federation, the study examined the top 100 retailers by sales, including digital. Retailers that trade entirely online, such as Amazon, were excluded.

With consumers remaining price conscious and often reluctant to spend, some of the top ten retailers benefited from offering attractive bargains.

These included the off-price department stores, Ross Stores and TJX Companies, which were ranked sixth and tenth respectively.

Both retailers bought excess inventory from other chains and then sold it on to consumers at lower prices. Department store chain Nordstrom, ranked eighth, also sold its inventory at a discount via its off-price store, Nordstrom Rack.

Nordstrom, like TJX Companies, has also opened online stores, sometimes by acquisition, which helped to boost sales growth.

The addition of new stores can also be a cause and the study found that most of the top ten had increased the number of their outlets.

AT&T Wireless and Foot Locker, the sports and footwear retailer, were the only two that did not add stores, but they are expected to invest substantially in this area over the next few years.

Alexandra Mansfield, global manager at Kantar Retail, concluded that "US shoppers are complex, disparate, knowledgeable and demanding; retailers that are attuned to consumption habits are succeeding".

Data sourced from USA Today; additional content by Warc staff