whisper number
n. An unofficial forecast of a company's earnings based on rumors and other unsubstantiated sources.
Examples
1999
Intel's earnings were far ahead of the $ 1.07 a share expected by Wall Street analysts surveyed by First Call.

The results even surpassed the "whisper number" of $ 1.10 a share circulated among traders following Intel's news in November that its results would be higher than analysts were projecting.
—“Profits at Intel, Yahoo Beat Wall St. Forecasts,” Los Angeles Times, January 13, 1999
1998
Whisper numbers were a U.S. invention, it appears, because of the enormous emphasis placed on earnings, as opposed to other measures of corporate performance. Wall Street's so-called momentum players adore companies that report constantly rising quarterly profits. When the trend is broken, they abandon the stock in droves, often with savage results. One Canadian analyst said: "In the U.S., there is an absolute preoccupation with quarterly numbers, especially in the tech sector. Without a whisper number, you can get destroyed."
—Eric Reguly, “Whisper numbers creep into Canada,” The Globe and Mail (Canada), May 29, 1998
1995 (earliest)
"Net income [for the quarter] was $ 168.7 million, or 59 cents per share," Carter read from a press release, "vs. $ 98.8 million, or 37 cents per share, during the first quarter last year." The per share figure was up a remarkable 59%; more important, though, it handily beat Wall Street's published estimates, which had been around 55 cents a share. It even beat the "whisper number" that had been quietly passed around by some of the analysts in the previous few days, as they realized their published estimates had been too low. The "whisper number" had been 57 cents.
—Joseph Nocera, “Cooking with Cisco,” Fortune, December 25, 1995
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