WorksheetFunction.Forecast_Linear method (Excel)

Calculates, or predicts, a future value by using existing values. 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 linear regression. You can use this function to predict future sales, inventory requirements, or consumer trends.

Syntax

expression.Forecast_Linear (Arg1, Arg2, Arg3)

expression A variable that represents a WorksheetFunction object.

Parameters

Name Required/Optional Data type Description
Arg1 Required Double x - the data point for which you want to predict a value.
Arg2 Required Variant known_y's - the dependent array or range of data.
Arg3 Required Variant known_x's - the independent array or range of data.

Return value

Double

Remarks

If x is nonnumeric, Forecast_Linear returns the #VALUE! error value.

If known_y and known_x parameters are empty or contain a different number of data points, Forecast_Linear returns the #N/A error value.

If the variance of known_x parameters equals zero, Forecast_Linear returns the #DIV/0! error value.

The equation for Forecast_Linear is a+bx, where   Formula   and   Formula   and where x and y are the sample means AVERAGE(all known_x) and AVERAGE(all known_y).

Example

Dim instance As WorksheetFunction
Dim Arg1 As Double
Dim Arg2 As Object
Dim Arg3 As Object
Dim returnValue As Double

returnValue = instance.Forecast_Linear(Arg1, Arg2, Arg3)

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