Flight only price ranges are current just about every 24 hrs and so are exact when printed. Flights at these price ranges are constrained and will market out immediately. To calculate day by day ordinary selling prices, KAYAK will take all prices for day after day just before departure throughout https://www.diigo.com/item/note/aa9i2/toer?k=e0117e85e0a1f5dcbd81d6e2fe5c001e