2 Replies Latest reply on Jan 11, 2017 2:12 PM by Tyler May

    Calculation Rounding Error

    Chris C

      I'm starting a separate topic that stemmed from a suggestion Shinichiro offered on a previous question I had regarding calculating the sale differences from the week prior.

       

      Now I would like to know if it is normal for calculations in Tableau to have significant rounding errors.  The percent difference formula is \

      (Sales - Last Week Sales) / Last Week Sales)

      A positive value means the value increased from last week, negative means it decreased.  Below is a screenshot of snippet of the view, followed by the expected values calculated in Excel.

      The percentages in red are values off by more than +/- 1%

      The difference is more apparent when comparing smaller values.  Without even using a calculator, I could easily tell the percentages were not correct.  The differences are roughly +/- 6 to 18%

       

      I'm using version 10.1.1