6 Replies Latest reply on Sep 22, 2013 1:57 AM by Jonathan Wilkendorf

    Parameter controlled projections shown with chaotic historical data

    Jonathan Wilkendorf

      I need help determining a method for adding parameter controlled projecions with historical data in a view.  I can do this easily in Excel (with a static parameter) but have searched for days on this forum and have not found a solution that works.  I have tried PREVIOUS_VALUE and LOOKUP functions as you can see at: http://public.tableausoftware.com/views/TestSeparate/Test3?:embed=y&:display_count=no

      In my simplistic example below, I intend to have a parameter control for the user to select the percentage rate so they can see how the future projection would look with that rate, while also still displaying the historical values in the same view.  The real historical data I will use is highly variable/chaotic so the Tableau 8.0 forecasting functionality is not available as an option and is not what I need in any case.