1 Reply Latest reply on Mar 3, 2016 8:43 AM by Paul Sherras

    Date format error

    Toby Close

      Hi all,


      I have imported a large set of data from Excel that include birth years for each entry.


      The birth years are currently formatted as a whole number, and vary in format between:



      86 (as in 86 A.D.)



      Tableau won't recognise these as dates and changes them all to years between 1899 and 1909. 


      I can use DATE("01/01/" + STR([Birthyear])) to recognise dates between 100 and 1016 correctly, but any years before that are either null or have 19 ahead of them (e..g 86 goes to 1986).


      I am new to Tableau but haven't found an answer to this problem despite searching.


      Thanks in advance!

        • 1. Re: Date format error
          Paul Sherras

          Hi Toby,


          Looking at the way Tableau formats dates, anything pre 1900 is coming through as - number and turn to nulls at 400AD.


          I got the numbers a little bit wrong, apparently there are more leap years than one in four (who knew?!), but please find attached a workbook reviewing this:


          With this in mind, I'm not sure whether tableau is currently able to do what you would lke


          Kind regards,