Summary object

The Summary object icon (list at top of rectangle) summary object displays a summary of records in a specified table. By default, it shows the total number of records, but it can be configured to provide a different numerical summary of a specified field, for example the average or number of unique values.

Claris Studio, Summary

What's this in FileMaker?

The summary object is similar in concept to a summary field in FileMaker Pro apps, except that its value isn't affected by its location in a view.