IMO a few things to consider
1. if the box is a user request, consider discussing alternatives for the purpose - I find many report requests are based on a unfounded assumptions of what the user thought to be an easy thing to do. They often are open to design changes that might handle a function of the report better than what they were able to think, or a formatting issue just ultimately is not worth the time and money spent to get it so they drop it.
2. reconsider adavis' suggestion but using top and side text borders that can handle conditional suppression in the header and side and bottom text borders in the detail section
3. Use the group select to exclude groups not meeting your condition entirely from the printed report. This would remove the header, detail and footer for the entire group.
Edited by DBlank - 09 Jan 2015 at 8:55am