Thanks for the reply, much appreciated.

My numbers run in rows 2 to 151 (headings in top row). I used
=FORECAST(C2,B2:B151,A2:A151) but it isn't the expected value.

I filled column C with my mid values (1.15,1.25 etc to 15.5) and used
column D for the formula to calculate the values corresponding to the
points in column C.

I might not be understanding the FORECAST funciton correctly however.
I only need to estimate between 1.1 and 1.2, for the 1.15 value, rather
than using the entire set of data to estimate.


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Micronaut
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