To calculate monthly regular charges, KAYAK will take all prices for on a monthly basis over the past year for round-vacation flights from London to Atlanta, eliminates the top 0.1% to account for outliers, and then usually takes the median of all values for monthly. These are the airlines KAYAK https://businessclassflightstonewyork.blogspot.com/2024/09/5-most-luxurious-hotels-in-world.html