Hi there,

I have two columns - Industry Code and Market Cap. I want to create a
summary table for average market cap and standard deviation for certain
Industries. However, there are like 20 different industry codes and I didn't
exactly feel like doing it manually for 20 cells. I tried out this formula
first:

{=STDEV((--($E$2:$E$296=K17))*$F$2:$F$296/1000000)}

Using it an array - the Ctrl+Shift+Enter thing. That didn't work out too well.

Cells E2:E296 contained the Industry Code column. Cells F2:F296 contained
the market capitlisations, while K17 was one of the 20 industry codes.

I think the reason why it didn't work (apart from probably wrong usage of
the double negatives on my part) was that it produced zeros for the companies
that I didn't want to include, which could screw up the STDEV calc, since it
includes any zeros in the calculations.

Is there any way around this?

I thought there might be another way by using standard deviation = square
root (expected value of x^2 - (average of x)^2 ) but couldn't really figure
out how to do a conditional squared sum. Is there of a way of doing that?

Thanks in advance,

Iwan J