

Q: What are "whisper numbers" and are they important?

A: The term "whisper number" returns to investors' vocabularies during bull markets. And with stocks amid a big-time rally, investors that haven't been hearing about whisper numbers should expect to, soon.

Whisper numbers are unofficial and unpublished estimates of what investors really think companies will earn. During bull markets, investors may pay more attention to whisper numbers than they do the official estimates from analysts.

A recent example of when the whisper number seemed more important than official earnings estimates was with social-networking company Facebook. The company reported earning an adjusted 17 cents a share the fourth quarter, which beat the 15-cents-a-share profit forecast of analysts, says S&P Capital IQ. Despite beating the profit forecast, the stock fell about 1% on the first day of trading after the news release on Jan. 31.

The stock decline was even more puzzling since Facebook not only beat earnings expectations, but showed more progress in mobile. The number of mobile active users of Facebook grew 57% as of December. For the first time, the number of active users on mobile devices topped the number using the Web.

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A reason the stock didn't rocket higher, though, was that quietly investors were expecting a bit more from Facebook during the quarter. The whisper number for Facebook was 17 cents a share, says, which the company matched. That wasn't enough to get the stock soaring higher.