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How to Use Existing Value in a Column to Predict when a Specific Value Will be Reached or Exceeded
It has been decades since I use Excel on a daily basis; so I have forgotten a lot that I once knew. I use it nowadays only for household tracking. I have a workbook wherein I track electricity c...
Let's say you have dates (or day numbers) in A2 and down, and meter readings in B2 and down.
Today (the 7th of April), you'd have data in A2:B8.
The day when 100 is reached is given by
=LET(x, A2:A8-A2+1, y, B2:B8, parms, LINEST(y, x), (1000-INDEX(parms, 2))/INDEX(parms, 1))