Use criteria to calculate slope and intercept?

is there away I can calculate the slope only if a criteria in a third column is met.

{=AVERAGE(IF($G$162:$G$1217=G162,$Q$162:$Q$1217))}

Essentially doing what the above does except calculate the slope and intercept. The third column is the problem for me i guess (x's, y's, and criteria column a)

any help would be appreciated

Hi,

Have you tried slope() and intercept() functions ?

HTH
Carim

The slope and intercept functions do not allow the specification of criteria as far as i know...for the entire data set they work fine but i want to be able to calculate different slopes and intercepts based on certain categories listed in a third column

I think what Carim was suggesting was to use an IF function within the SLOPE and INTERCEPT function just like you used in the AVERAGE function. Technically, the AVERAGE function doesn't inherently allow to test for criteria, either, but you next the IF function within the AVERAGE function and you find that you can. SLOPE and INTERCEPT should work in the same way.