To determine every day common price ranges, KAYAK can take all selling prices for daily before departure during the last 12 months for flights from London Heathrow Airport to Austin, removes the very best 0.1% to account for outliers, after which normally takes the average of each of the values https://www.evernote.com/shard/s668/sh/d1a73892-71c2-9129-074f-589e65cdabcb/GPo8jiDtbWb8PfjoXyNavqJxyPsP0bPCthoUYc7iaeM-5aNTVZCPfZB8jg