The report should be based on a query, not the table itself, for this very type of reason. Your query would limit the records returned where the Percentage is less than 100. AFAIK, percentage is not a problem/reserved word, but I would not use percent. Suggest you replicate the table fields you need with a query. Note: you would not be hiding the rows - you would not be bringing them back. If hiding is what you MUST do, I'm not sure that's possible, even if using code for the report format section On_Format event or format.property.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.