Conditional statements

[wc115]

Hi,

I want to find the standard deviation on a certain set of data with conditional statements.
For example I want to find the standard deviation of Sales only if the Rank = A and Month = 1.

Rank	SALES	MONTHS
A	1	1.00
A	10	1.00
A	2	1.00
A	10	1.00
A	1	1.00
B	3	1.00
B	3	2.00
B	3	1.00
B	3	2.00
B	3	1.00
B	3	2.00
B	3	1.00

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This is what I came up with:
=STDEV(IF(AND(A2:A6=H2,C2=1),B2:B6))

It works if I only take the first 5, as soon as I take the rest my result changes but it should not because of the conditions.

Any help would be appreciated.

Thanks!

 

[helpexce]

Try this one.

=STDEV(IF($A$2:$A$13="A",IF($C$2:$C$13=1,$B$2:$B$13)))

Confirm with Ctrl+Shift+Enter and not just Enter.

 

[AhoyNC]

Try.
This is an array function and must be entered with CTRL-SHIFT-ENTER.

Excel Workbook
	A	B	C	D	E	F	G	H	I
1	Rank	SALES	MONTHS		StDev.
2	A	1	1		4.764452			A
3	A	10	1
4	A	2	1
5	A	10	1
6	A	1	1
7	B	3	1
8	B	3	2
9	B	3	1
10	B	3	2
11	B	3	1
12	B	3	2
13	B	3	1
14
Sheet