To calculate month-to-month average selling prices, KAYAK normally takes all costs for on a monthly basis during the last calendar year for round-journey flights from London to Atlanta, eliminates the best 0.1% to account for outliers, and afterwards will take the median of all values for on a monthly basis. https://premiumeconomyflightstoamritsar.blogspot.com/2024/12/5-tips-to-grab-cheap-business-class.html