EASY Access 97 Count Question

I have a table with 2 fields. Name (Text) and Present (Yes/No Checkbox). There are 6 records, three are checked.

I made a report with both fields and was able to get a count of all names (6).
Now I want to count only the check boxes. I made a calculated field called checked and put =(IFF([Present] = “-1” , 1, 0))
I put this field in the detail section.

NOW, in the report Footer, I want to Count all the “checked” records. I keep getting a Parameter box for the checked field.

What am I doing wrong???

Thanks,
Alan