5 Replies Latest reply on Nov 20, 2016 12:48 PM by Simon Runc

    MoM- Same Calculation but different results

    sreevidya.yandra

      Hi Everyone,

       

      I have been trying to calculate MoM using the super store dataset.

       

      There are two approaches that I have tried:

      1. Using Quick Table calc.

      mom table calc.png

      2. Using calculated field:

      mom calc field.png

       

      Issue is when i add both these calculations to the same sheet, they yield different results. One right and one wrong.

       

      I am not able to understand where I went wrong. I have attached my workbook to this discussion incase anyone would like to have a look.

       

      Could someone help me in this fix.

       

      Thanks,

      Vidya.

        • 1. Re: MoM- Same Calculation but different results
          Johan De Groot

          Hi

           

          the problem is the difference in how these Table Calculations are calulcated: the one from the wizard uses a only 'month' - and disregarded the category. The 'hand made' one uses 'table down (probably what you need).

          Attached workbook (Tableau 10.1 version of your workbook) shows the right values with a 'standard' table calculation - using pane down, but you can also use 'specific dimensions' and 'month' + 'category'

           

          Hope this solves your problem - otherwise let me know!

           

          Kind regards,

          Johan de Groot

          • 2. Re: MoM- Same Calculation but different results
            Simon Runc

            Hi Sree,

             

            So the difference comes from the Compute Level in the Table Calculation being different...

             

            When you specify to Compute Using = Month...it uses Month to determine the %age Difference and restarts this calculation each Category (as Category isn't specified in the Compute Using the calculation get's partitioned on Category).

             

            When you specify to run Table Down..it adds all "Downward" dimensions in the Compute Using, so doesn't restart the %age Difference Calculation each Category (it just keeps the % Diff calculation running down the page).

             

            If you set the Compute Using to be Pane down...as the Category is in the Pane, it does the same as the Compute Using = Month, as now only the Month is in the Compute Using.

             

             

            Hope that makes sense.

            • 3. Re: MoM- Same Calculation but different results
              sudhakar reddy

              sree vaidya,

               

              Please find the below screenshot.you just need to change the format of number percentage to 2 decimal places.

               

              forums2.png

               

              hope this helps you.

               

              Regards,

              Sudhakar Reddy

              • 4. Re: MoM- Same Calculation but different results
                sreevidya.yandra

                Hi Simon,

                 

                Thank you for clarifying the difference between pane down, and table down. It did help in getting a better picture of what to do next.

                 

                Have a great day!!

                 

                Thanks,

                Vidya.

                • 5. Re: MoM- Same Calculation but different results
                  Simon Runc

                  No problem, glad it helped.

                   

                  I would add that although the formatting was part of it, your 2 calculations were returning different results. Although they both start the same, when you get to the next category there is a difference...the Compute Using Month re-starts, whereas the Table down keeps going, giving the MoM for the last month of Furniture, to the first Month of Office Supplier.

                   

                  If you look at my screen grab, I've captured the difference.