What's the best way to display the count of records related to a record in FM 8?

[Randy Siler]

Hi,

What's the best way to display the count of records related to a  
record in FM 8?

For instance I have a table Sections
        that defines sections of a workshop at a conference

and we make SectionAssignments
        that put a person in a section which has some number of available seats

I would like my field SeatsTaken in Sections to automatically be  
equal to the number of related SectionAssignments.

so that my seatsAvailable calculation can be seatsAvailable =  
seatsTotal-seatTaken (where seatsTaken is dynamically representing  
the number of related SectionAssignments.

Thanks much,