I wish the time horizon on this matched the time horizon on which tickets are available. It seems to be about a month short when I compare to directly shopping for flights on airline websites.

Granted that shouldn't matter quite as much for the "when will fares increase" question, since they have to have a baseline to evaluate the increase magnitude, but it sure matters simply for the "I'm planning to fly in for a popular event a year from now and I know tickets are being snapped up so I want to compare fares for flights as soon as they become orderable" scenario.