1 Reply Latest reply on Jul 8, 2013 5:50 AM by adam.medcalf

    Inverting a % of total running sum table calculation


      Hi there,


      In my analysis I have used a "% of total running sum" table calculation built up via using a calculation type of "running total" summarzing values using Sum across the table, followed by "performing a secondary calculation on the result" consisting of "percent of total".


      This means I can see that for example up to 15% of my records happen by month one, 30% by month 2 etc.


      However I need to present this in terms of how many records DON'T happen in month 1, 2 etc. i.e. instead of the values running 15%, 30% etc. I want it to show 85%, 70% etc. inverting the curve (like a decay curve). In Excel you would do this by charting 1-[the value]


      I hope this explanation makes sense, or perhaps the picture below helps!



      I can't figure out how to do this. I tried "customize" the table calculation but the dialog box says that is not supported.


      Most grateful for any help on this! It seems like it would be simple but I am clearly missing some obvious useful option or simple calculation here...I have to use Powerpivot as my datasource, and Tableau 8.02 if it makes a difference.

        • 1. Re: Inverting a % of total running sum table calculation



          Managed to eventually solve it...and here's the answer in case anyone else ever has anything similar.


          Instead of going through the table calculation menu, insted create a normal custom measure.

          Use a formula like this:


          1-(RUNNING_SUM( [Count of distinct customers] )/ TOTAL([Count of distinct customers]))

          and format as a percentage.


          At least it seems to work in the few examples I tested!