I have a table whose records represents club attendee stats per month which includes (among several other fields) 5 fields representing the number of attendees per week of the month. Eg. Week1 = 20, Week2 =22 etc.

I need to create a query that tells me the running average amount of weeks (not attendance) all clubs met per country.  Some of the weeks have zero attendance, so it's not a straightforward calculation. Note: There are no null values, weeks with no attendance have a "0" in them.

Fields/Columns are: