Simple Slope Formula Question

Hello All,

I am having trouble getting a simple slope function to work. I want it to just take the slope of the y values that have above a set value (I tried to use a conditional, but it didnt work so I ended up here!). In this workbook I have attached, that set value is 400. Just as a side note, the slope function must be used, or some type of function that takes every data point into account, and I do not want to just use a conditional to copy over the data that is over 400 in the next column and then take the slope of that...thats cheating!

This may be an easy question, but I would appreciate the help!

Thanks!

=SLOPE(IF(B2:B26>=400, B2:B26), A2:A26) ~ 2.8



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