For instance, various airline systems might host their air fares services in a registry, and a generic client could discover all such services and find the cheapest air fares provided by the airlines.

But because tickets were more available, and air fares and other things were cheaper, some people were able to afford the Derby who would otherwise have been priced out.

A big shift in passenger Numbers would be more likely if airlines had to pay the same taxes that train operators do, namely value-added tax and a tax on fuel, both of which would push up air fares.