In this Jan. 26, 2011 photo, Terri Lewis installs a fan on a diesel engine on the Volvo truck assembly line at the Volvo plant in Dublin, Va. The work force was more efficient last year with productivity rising at the fastest pace in eight years while labor costs fell for a second straight year, something that hasn't happened in nearly five decades. (AP Photo/Steve Helber)
In this Jan. 26, 2011 photo, workers talk as they work on a diesel truck engine on the Volvo truck assembly line at the Volvo plant in Dublin, Va. The work force was more efficient last year with productivity rising at the fastest pace in eight years while labor costs fell for a second straight year, something that hasn't happened in nearly five decades. (AP Photo/Steve Helber)