Those sweeps months are November, February and May. Even here, just outside of L.A. the networks put there money into those times in order to hype the numbers. Thus the buy itself is numbers based.
Some day radio and TV will be able to sell based on quality and not blind CPMs and CPPs. This is why all of the radio stations jump on what ever format is hot, and your favorite TV show gets duped after 4 episodes. (anybody miss the original Law & Order. I see they've canceled the L.A. version.)
