/tags/previous_value/ Recent content in PREVIOUS_VALUE on Bitfern Hugo en-nz Fri, 10 Jan 2020 07:47:58 +0000 /blog/previous_value-in-tableau/ Fri, 10 Jan 2020 07:47:58 +0000 /blog/previous_value-in-tableau/ <p>Late last year I started to actively help out on the Tableau Forums. What a great decision! I’d forgotten how much fun it could be to (1) pick up a discrete challenge; (2) help others out; and (3) learn so much more in the process.</p> <p>One of the questions I recently chipped in on was about <!-- raw HTML omitted -->circular references in a sequential calculation<!-- raw HTML omitted -->. The background to the question is really interesting and I ended up spending a few hours digging into epidemiological models, but that’s a different story! Whilst trying to help I took a fresh look at the <strong>PREVIOUS_VALUE</strong> function in Tableau. I have to admit, prior to this I had thought that PREVIOUS_VALUE(x) was just the same as LOOKUP(x,-1) … turns out that isn’t the case!</p>