Suppliers outperformed automakers and retailers in all three periods.
"Japanese suppliers have seen increased business because of Japanese vehicle manufacturers moving operations to different countries, and they need suppliers over there," says Aaron Witalec, transaction services senior associate for PricewaterhouseCoopers.
Aisin Seiki Co. Ltd. posted the highest return for the quarter that ended Sept. 30, up 18.7 percent. The Toyota Motor Co. affiliate has been diversifying its customers beyond Toyota to minimize risk.
Tokai Rika Co. Ltd., another Toyota affiliate, topped the 12-month ranking, up 114.1 percent.
Tenneco Automotive Inc. showed the highest value for three years, up 523.8 percent.
Intermet Corp. ranked lowest in all three periods. The company filed for Chapter 11 bankruptcy protection last month, in large part because of its dependency on scrap steel.
Suppliers have been driving high merger-and-acquisition activity again this year. Through September, nearly 450 transactions were recorded, valued at $15 billion. That's on pace with last year's high total activity, valued at about $20 billion.
"With the vehicle manufacturers' pressure to reduce costs, suppliers are using acquisitions to spread overhead costs over greater volume," PricewaterhouseCoopers said in its analysis of the rankings. "Acquisitions may also help suppliers to produce integrated systems modules as vehicle manufacturers are demanding."
But Jay Singer, transaction services director for PricewaterhouseCoopers, warns that suppliers' superior returns are vulnerable.
"Vehicle manufacturers continue to bear the costs in sustaining volumes," he says. "It might be fair to say that we'll see that relationship change. Supplier returns will feel the pressure."
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