Instead of using STDEV(C1:C31) have you tried the learners way of using a
coma for the values and missing the cells that you do not require.

Example

STDEV(C1,C2,C4,C5 AND SO ON .......)

This works both with rows and columns, but, beware, it only allows 1024
characters in the formula and every character in between the brackets count,
yes, including the comas)

HTH


"JonR" <JonR@discussions.microsoft.com> wrote in message
news:4E961F70-3684-46C2-9E06-ADE6669AC569@microsoft.com...
> I'd think the easiest thing to do would be to hide column C. I'm assuming
> that you just don't like having it visible.
> --
> HTH
>
> JonR
>
>
> "Arne Hegefors" wrote:
>
>> Hello! I have a small problem. I have two columns, A and B. In these
>> columns
>> there are returns for different bonds. In column C I calculate the
>> diffence
>> between A and B (C1=A1-B1). In column D I want to calculate the standard
>> deviation of the difference dating 30 data points back. Thus, in D31 i
>> write
>> =STDAV(C1:C30).
>>
>> This all works fine. However I want to skip having the C column and make
>> the
>> calculations for the standard deviation of the dífference dierctly from
>> the
>> values in A and B. However I have not managed to do so. Please help me
>> out! I
>> know it does not sound worthwhile but having the extra column really
>> messes
>> up my spreadsheet! Any help appreciated! Thanks alot!