By Caroline Valetkevitch NEW YORK, Oct 19 (Reuters) - U.S. earnings started the quarter on the wrong foot, and things have only gotten worse. Expectations for the third quarter were dismal, with forecasts for a decline in profits from a year ago. But a recent flurry of high-profile reports has investors scowling at the weak revenue numbers, adding to worries about the state of the U.S. economy and the outlook for corporate America. "The earnings season is not looking very bright," sa