Ok... this might be impossible or otherwise crazy... but I'll ask anyway:

Is there a way to calculate standard deviation where only certain qualifying
data is analyzed?

I have a bunch of data... For example:

orderID Order $ Date # of Parts
w1234 $5 1/1/09 10
w1235 $10 1/1/09 5
w1236 $7 1/4/09 10

etc, etc (I have like 9k rows and my real data has more columns)

Currently I chew through this data using SUMPRODUCT to pull together
different groups. For example:
- Show me total order $ for "w1234" in 2009.
- Show me # of orders for "w1234" in 2009.
- Show me Avg. order $ for "w1234" in 2009.

My question is: Is there a way to calculate standard deviation in a similar
way? For example: Show me standard deviation of order $ for "w1234" in 2009.

I'm trying to avoid manually copying the qualifying entries into their own
sheet / area or using a macro. SUMPRODUCT kicks butt for this kind of thing
because you can just string together all sorts of criteria to analyze a pile
of data without moving or editing the pile.

I see that STDEVA accepts up to 255 unique references... but this would
require manually selected each cell... I want to give it parameters and let
it find the qualifying cells (in a given column of course) on it's own.

Any ideas?