Raising the Bar

Plot:

The main Cybrary is under attack. Hacker, disguised as an exterminator called the Verminator, has released a mysterious, fishlike cyberbug that is systematically destroying certain information - but Ms. Fileshare, the overworked Cybrarian is too busy to notice. While Hacker uses bar graphs to confuse the Cybrarian, the kids create bar graphs of their own to counter his contentions. Which graph will the Cybrarian believe? And what information is Hacker trying to destroy?