3 Replies Latest reply: Nov 29, 2016 1:58 PM by Jason Bassett RSS

    Creating an Exponential Decay

    Jason Bassett

      I am attempting to create a calculation that uses an exponential decay. In Excel, this is very easy since I can reference the cell that was calculated above the cell that is currently being calculated. Here is what it looks like in Excel.

        

      Exponential Rate of Decay0.6
      Decay Calculation=Current Balance * EXP(- Rate of Decay / 12)
      DateBalance
      1/1/2016100.00
      1/2/201695.12
      1/3/201690.48
      1/4/201686.07
      1/5/201681.87
      1/6/201677.88
      1/7/201674.08
      1/8/201670.47
      1/9/201667.03
      1/10/201663.76
      1/11/201660.65
      1/12/201657.69

       

      I have tried the above() function but it will not calculate the values. I am guessing since there is a calculation inside of a calculation it is getting lost. Here is the calc:

                  above((Sum([Static Raw Value])/Sum([Static Number of Sites])/Sum([Static Number of Days In Month]))

                  *exp(-.6/12))*exp(-0.6/12)

       

      Anyone have any ideas? Any help would be appreciated.