3 Replies Latest reply on May 29, 2012 6:24 PM by hub.yoo

    Calculating a Metric

    Elizabeth Coleman

      Hello, 

      I need help in calculating a Metric that shows the percentage of inventory that is available for installation versus what is scheduled (forecasted) for installation the in the next month.  In the past I calculated the formula in Excel;  here's what I need to calculate:  calculate the inventory at the end of the month divided by the Forecast for the next month.  My dilemma is that I'm working with 2 plus years of data instead of one month data; I don't know how to do this in Tableau.    I have a worksheet that contains the forecast for the next month and a worksheet that contains inventory at the end of the month.  At first glance, it seems easy just divide the inventory by the forecast.  I tried that and it did not give me the results that I need.  How do I set up a formula to calculate the inventory at the end of the month divided by the the forecast of the next month.  Thanks in advance for any help. 

        • 1. Re: Calculating a Metric
          Tracy Rodgers

          Hi Elizabeth,

           

          The way to do this would probably be to use table calculations. For example:

           

          total(sum(installation))/total(sum(forecasted))

           

          Then, when this is placed on the view, right click on the calculation and edit how the calculation is computed (i.e. by Month). Hopefully this helps a bit!

           

          -Tracy

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          • 2. Re: Calculating a Metric
            Elizabeth Coleman

            Tracy, thanks for the reply but it didn't quite give me the answer that I'm looking for.  I need to see the inventory level vs. forecast for each Project Manager by month.  My data contains records for the past 3 years; I'm trying to see a trend by Project Manager. 

            • 3. Re: Calculating a Metric
              hub.yoo

              Hi Elizabeth,

               

              You might need to change it into an attribute or something. I was doing something similar where I needed to show current production vs scheduled production and the difference between the two. You would assume that it would be [Forecast] - [produced] would work as a calculation...

               

              Instead i had to use the following:

              ATTR([Goals]) - [RUNNING_SUM(SUM([Passing]))

               

              haha. im terrible at tableau. i get lucky sometimes though and people respond to my questions. If anything hopefully this bumps you up. Or you should post a mock up of your viz so some of the pros can take a quick look at it.