2 Replies Latest reply on Apr 6, 2012 9:53 AM by Allison Suarez

    Reference Line base on a calculation

    Allison Suarez

      I am trying to include an upper control limit on a run chart (line chart).  Can I use a calculation in a reference line?  I also can't get the calulation to work.  Here is what I am working with calculation wise. 

       

      Average (count(service request)  - - - - service request is a string (unique identifier for calls that come in)

      stdev (count(service request)

       

      Upper control limit calc = Average(count(service request) + (3*stdev(count(service request)))

       

      Based on the raw numbers I should get

      Average = 15.57

      stdev = 8.57

      UCL = 41.29

       

      I guess the better question is can Tableau do this for me though some sort of statistical analysis that I am not aware of?

      I attached a workbook below.

       

      Thanks for any help you can provide.