Long Term Perspective
Note that the spread between the Baa Corporate and the 10-year Treasury note is wider than the spread between the Aaa corporate bond and the Treasury security. This reflects market views of credit conditions among these lower rated corporate bonds.

Short Term Perspective
Yields on Baa rated corporate bonds decreased 22 basis points in November while the 10-year Treasury note yield dropped 13 basis points. When yields on lower rated bonds don't rise as much as yields on higher rated bonds, it suggests that default risk has diminished (usually this happens during an expanding economic period).