I'm working on using the new forecasting feature in version 8, and it looks like Tableau is automatically choosing how far back it will go to check for seasonal patterns. Right now, it is only going back 13 weeks, but I'd like it to actually check back to the prior year parallel period. Do any of you know how to configure Tableau to do this?
As an example, if my data consists of weekly numbers from Jan 1st, 2011 to March 21th, 2013, when Tableau generates a forward 13 week forecast, I'd like it to reference a span between February and March of 2012 to detect seasonality for the March 28th, 2013 forecast.
Any help is greatly appreciated. Thanks!
The forecast will look at all the data in the view, not just a specific portion. The following article gives all the forecast options and explanations:
Hope this helps!