Average of an average

[audbene]

Hi--Hoping someone can point me in the right direction.



I have a report based on an aggregate query. The table lists a bunch of survey questions. The query aggregates an average score for each question by month, and I have a report showing all those averages. So far, so good.

I want to have a calculated overall average. I've spent literally several days researching all the ways to do this and all of them end up doing exactly the same thing, showing me "#Error" instead of the average.

The only success I've had is adding a text box in the report footer with the following sample lingo. It works if I try to average 3 averages but consistently errors when I try to add a 4th. I need it to average 20 averages.

=Round(Sum([Avg Of Question1]+[Avg Of Question2]+[Avg Of Question3])/3,2)

I've tried:
Removing the Round(). No change.
Retyping the lingo several times to be sure I'm not making an error. No change.
Removing symbols from and shortening field names. No change.
Highlighting the fields I want to average and using the "Grouping and Totals" button. It's grayed out.
Banging my head against the wall. Surprisingly, that didn't work either.

Thanks

PS-I don't know what operating system I have.

[audbene]

QUESTION 2

This one gets even more complex.

Once I figure out how to calculate the average of the average, grouped by month, I've been asked to show each month's overall average on the report.

I tried building a subreport but am stuck because I can't find a solution to question 1.


Thanks again!!