Syntax. FORECAST(x,known_y’s,known_x’s)

Definition. This function returns the estimated value for a linear trend. The predicted value is a y-value for a given x-value. The known values are existing x-values and y-values, and the new value is predicted by using a linear regression. You can use this function to predict future sales, inventory requirements, or consumer trends.


  • x (required). The data point for which you want to predict a value

  • known_y’s (required). The dependent array or range of data

  • known_x’s (required). The independent array or range of data


If x isn’t a numeric expression, the FORECAST() function returns the #VALUE! error.

If known_y’s and known_x’s are empty or contain a different number of data points, the ...

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