finding unique related records

[tftedorr]

I have a database that tracks activities that households participate. Each time an activity is attended it is entered in the Activities database. I am creating a summary of the data in the Activity database and am able to get the total number of attendants for a particular series of activities, however I want to get the total number of unique households that attend. Some households attend multiple times, so I want that household to only be counted one time.

Any ideas of how to go about creating this so that I can summarize the number of attendants with the number of unique households in the same subsummary?

[Philland]

Is there a unique household identifier that you can use? Maybe a street address field where identical records can be identified?

Can a unique code be added on data entry? The first time a household record is created a qualifier field would be marked 1 and all additional records with that household would be zero's. That could then be used as a field to summarize.

Phil