Multiple tables on one page each with 3 calculation fields, tables interacting with each other

Hello,

I have a PDF with 3 tables on one page, see attachment. An instructor fills out each table with points for each listed item. I set up 3 calculated columns; a total for the number of items being graded on, a total for the number of -10 points, and a final total. I have found the tables interact with each other. For instance, if I fill out the first table with test points for each item and then do the same for the second table the totals start getting jacked up because somehow the tables are interacting with each other. I've verified several times that each total column is only using the appropriate table columns I've specified. Is there a fix for keeping tables from interacting with each other?