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Whisper Number or Forecast
A whisper number is an unofficial earnings estimate for a particular company that a stock analyst shares with clients to supplement the official published estimate.
If the company reports earnings in line with the official estimate when the whisper number has been higher, the stock price may fall anyway since investors were expecting something better.
The same is true in reverse. If earnings fall short of official expectations but meet a lower whisper number, the stock price may go up.