We will have a price that’s available on that flight, on that time, to you, the individual,” Delta president Glen Hauenstein told investors in November, having started to test the technology on 1 percent of its ticket prices.

Prices are based on Delta’s internal data, such as historical bookings, as well as external variables like weather and market trends.

According to a Fortune report, Delta is moving aggressively to let artificial intelligence determine what each passenger is individually willing to shell out for a ticket, with the goal of having 20% of all fares set this way by the end of the year.