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Creating an Objective Forecast - by Liam Bastick, Excel MVP

cuong's avatar
cuong
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Jul 31, 2019
For many, it’s that time of year again when budgets need to be dusted down and re-vamped. Those in finance spend sleepless nights reviewing minutiae and “normalizing” data before talking to their ope...
Updated Apr 24, 2020
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PeterBartholomew1's avatar
PeterBartholomew1
Silver Contributor
Feb 23, 2024

My experience is that the reality is

"If the target_date is chronologically before the start of the historical timeline, FORECAST.ETS returns the #NUM! error"

 

If the actuals are on a separate worksheet, it can be useful to reproduce the entire timeline on the calculation sheet or presentation layer.  That requires the array 'timeline' to be used in place of an implied scalar 'target_date'.  Maybe it is living dangerously, but I think FORECAST.ETS will interpolate past data as well as forecasting future values.

 

= FORECAST.ETS(timeline, actualsData, actualsDate)