Why wage hikes could spell trouble for Wal-Mart

An employee in a Walmart store.
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Wal-Mart's plans to hike employee pay could spell trouble for the world's largest retailer, according to the latest research.

Research firm Markit says Wal-Mart is likely to underperform as a direct result of its wage hikes. The company announced last week it would increase the pay for 500,000 of its lowest paid workers, first to $9 per hour in April then to over $10 in February 2016.

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Markit said the move will raise Wal-Mart's salary bill by $1 billion and impact the revenue generated per employee—a measurement that Markit said investors tend to reward.

"What the data is showing us is that stocks that have low revenue per employee metrics have underperformed over the last few years," Relte Stephen Schutte, assistant vice president and analyst at Markit, told CNBC via email.

"The market has punished firms which score poorly on this key operating metric and a wave of wage inflation could see this trend continue in earnest, especially for firms with large, relatively inefficient workforces, " he added.

Wal-Mart shares took a near 3 percent dive following the wage announcement last Thursday and are down 2 percent this year.

Since the Wal-Mart move, speculation has increased over whether other big box retailers would follow suit. Off-price retailer TJX on Wednesday announced a similar plan to boost pay, and Target said it was "very focused on ensuring we have competitive wages."

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"Some retailers will be forced to join in the game," CNBC retail analyst Stacey Widlitz said, "and that will again pressure the bottom line of earnings for some of these retailers."