Another issue that will be closely monitored by Moody's is the evolution of U.S. borrowing costs in the next few years.
The agency would see it as normal if yields paid on U.S. 10-year Treasury notes rise from the currently "abnormal level" of around 2.6 percent to near 4 percent by 2012 and almost 5 percent by 2016, Hess said, referring to the economic assumptions of the Congressional Budget Office.