Age Formula

Hi Hans,

Thanks for reaching out. I tried your formula and ended up with the same result of "#VALUE!"

I formatted both the date of birth & date of op cells as custom "dd-mmm-yy". Excel will assume all years under '26 to be 2026, yet when I enter a 4 digit year the that is preserved. Except for the last 3 DOB in the attached extract of my 6 oldest patients at the time of their surgery: I suspect that is the source of the error.  I have been unsuccessful in my attempts to get Excel to display those last 3 DOB as it does the first 3

It might be the size of the spreadsheet >17000 patients in it, but that doesn't really explain why some DOB display as entered and others don't.

Tried attaching the extract as an .xlsx but the upload is not supported. So 2 pictures uploaded: 1 displaying cell with your formula in, the other with a different cell with the original formula.

If you have the time, I'd be most grateful for any advice you can offer me.

RoryCScott