Colloquy summarizes the current state of frequent flyer miles:

By the end of 2004, almost 14 trillion frequent flyer miles had been accumulated worldwide. According to a new analysis by The Economist magazine, the global stock is worth more than $700 billion, more than all the US dollar bills in circulation.



More than 130 airlines issue them, handing out more than 14-million free flights annually. So many different types of frequent flyer miles are in circulation that consultancies have sprung up in Europe and America devoted solely to helping people get the most of their portfolio.



Ravindra Bhagwanani, founder of Frankfurt-based Global Flight Management, said: “[Frequent flyer] miles are a game you have to play. If you want to play a game successfully, you need to know the rules.”

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More than 120 million people belong to frequent flyer programs worldwide. The record for the biggest individual account is just over 23-million miles.