Combined Standard Deviation of Two Separate Columns of Data

[JeffFinnan]

I can get the average of two columns of data:

=(SUMIFS(D6:D2000,D6:D2000,"<>#N/A",A6:A2000,"Cm")+SUMIFS(I6:I2000,I6:I2000,"<>#N/A",K6:K2000,"Cm"))/(COUNTIFS(D6:D2000,"<>#N/A", A6:A2000,"Cm")+COUNTIFS(I6:I2000,"<>#N/A", K6:K2000,"Cm"))

where I am selecting for those values that are Cm.

Likewise I can get the standard deviations of the separate columns:

=STDEV(IF(A6:A2000<>"Cm",IF(ISNUMBER(D6:D2000),D6:D2000)))
=STDEV(IF(K6:K2000="Cm",IF(ISNUMBER(I6:I2000),I6:I2000)))

How can I get the standard deviation of the combined columns much like I can get with the average?

Thanks,
Jeff

 

[Domenic]

Try...

=STDEV(IF(A6:A2000="Cm",IF(ISNUMBER(D6:D2000),D6:D2000)),IF(K6:K2000="Cm",IF(ISNUMBER(I6:I2000),I6:I2000)))

...confirmed with CONTROL+SHIFT+ENTER.

Hope this helps!