In the municipal bond market, where cities and states go to borrow money, attention was focused on a ruling that allowed Detroit to enter bankruptcy to relieve its crushing debt. Detroit is the largest public bankruptcy in U.S. history.Tuesday's ruling was widely expected, so it had little immediate impact on the market, said Patrick Stoffel, a municipal analyst at Wells Fargo Advisors. More crucial for the wider market will be how the judge rules on the city's plan for exiting bankruptcy, he said. A ruling that allows the city to repay only a fraction to the holders of its so-called general obligation debt could push up borrowing costs for cities in the future. In company news: Yum Brands fell $2.10, or 3 percent, to $75.61. The owner of KFC and Taco Bell said sales in China, a key market for the company, have been sluggish because of concerns among Chinese customers about food safety. Abercrombie & Fitch rose $1.97, or 6 percent, to $35.99. The stock of the teen clothing store owner rose after an activist shareholder, Engaged Capital, sent a letter to the company demanding that CEO Michael Jeffries be replaced.