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=FORECAST()

Predicts a future value based on a linear trend (the legacy FORECAST.LINEAR)

Applies To: Excel for Microsoft 365Excel for Microsoft 365 for MacExcel 2024Excel 2024 for MacExcel 2021Excel 2021 for MacExcel 2019Excel 2016
=FORECAST(x, known_y's, known_x's)
Hover argument names in the table for details.
Output typeNumber
Popularity35 / 100
VolatileNo
Dynamic ArrayNo
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◧ Arguments

ArgumentTypeRequiredDescription
x Number Required The value to predict
known_y's Range Required Known result values (y)
known_x's Range Required Known predictor values (x)

▣ Examples

Example 1 =FORECAST(13, B2:B13, A2:A13)
Example 2 =FORECAST(80, C2:C25, B2:B25)

§ Remarks

  • اگر x غیرعددی باشد، FORECAST خطای #VALUE! را برمی‌گرداند.
  • اگر known_y's و known_x's خالی باشند یا تعداد نقاط داده آن‌ها متفاوت باشد، FORECAST خطای #N/A را برمی‌گرداند.
  • اگر واریانس known_x's صفر باشد، FORECAST خطای #DIV/0! را برمی‌گرداند.
  • معادله پیش‌بینی FORECAST برابر است با a+bx که در آن a و b میانگین‌های x و y هستند.

✦ Tips

  • In the arguments, the y values (results) come first, then the x values (predictors).
  • It only considers a linear trend; for seasonal data FORECAST.ETS is more suitable.
  • اگر واریانس known_x's صفر باشد، FORECAST خطای #DIV/0! را برمی‌گرداند.

⚠ Common Errors

#VALUE! مقدار x غیرعددی است.
Fix: برای x مقدار عددی وارد کنید.
#N/A The two ranges do not contain the same number of data points, or one of them is empty
Fix: Make the two ranges the same size
#DIV/0! واریانس known_x's صفر است.
Fix: مطمئن شوید مقادیر known_x's یکسان نیستند و حداقل دو مقدار متفاوت دارند.

⇄ Related Functions

=INTERCEPT() Calculates the point at which a line will intersect the y-axis by using existing x-values and y-values. The intercept point is based on a best-fit regression line plotted through the known x-values and known y-values. Use the INTERCEPT function when you want to determine the value of the dependent variable when the independent variable is 0 (zero). For example, you can use the INTERCEPT function to predict a metal's electrical resistance at 0°C when your data points were taken at room temperature and higher. =SLOPE() Returns the slope of the linear regression line through data points in known_y's and known_x's. The slope is the vertical distance divided by the horizontal distance between any two points on the line, which is the rate of change along the regression line. =FORECAST.ETS() Calculates or predicts a future value based on existing (historical) values by using the AAA version of the Exponential Smoothing (ETS) algorithm. The predicted value is a continuation of the historical values in the specified target date, which should be a continuation of the timeline. You can use this function to predict future sales, inventory requirements, or consumer trends. This function requires the timeline to be organized with a constant step between the different points. =TREND() The TREND function returns values along a linear trend. It fits a straight line (using the method of least squares) to the array's known_y's and known_x's. TREND returns the y-values along that line for the array of new_x's that you specify. =FORECAST.LINEAR() Predicts a future value based on the linear trend of past data

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