The rule of thumb that I've heard was that anything about a month out represented the 'normal' price.
If you're buying a ticket for a flight less than a month away, the prices start to rise dramatically as the flight date draws nearer. But if you're buying a ticket for a flight more than a month away, it's more-or-less the same price as a flight that's a month away. [1]
So absent any other information, the 'normal' price can help people ballpark costs more quickly, something I'd expect to be statistically more common than actually searching to book a specific flight on specific dates.
[1] With exceptions for destinations with very defined/popular seasons, holidays and things like that.
If you're buying a ticket for a flight less than a month away, the prices start to rise dramatically as the flight date draws nearer. But if you're buying a ticket for a flight more than a month away, it's more-or-less the same price as a flight that's a month away. [1]
So absent any other information, the 'normal' price can help people ballpark costs more quickly, something I'd expect to be statistically more common than actually searching to book a specific flight on specific dates.
[1] With exceptions for destinations with very defined/popular seasons, holidays and things like that.