This project visualizes cancellation rate and largest cancellation reason for the 25 busiest airports by number of flights in 2008. About two-thirds of these 25 airports are located in the states by coastline, indicating the geographic advantage of coastal cities in the hub-and-spoke airline system. As indicated by the bubble size, on average, airports in the west coast have lower cancellation rates as compared to those in the east coast. Nearly two-thirds (16 out of 25) of these hub airports reported carrier-related causes including aircraft maintenance, baggage loading, and fueling, etc.,(read more here), as the main reason for cancelled flights. (Data Source)