I, for one, have always taken this to be some very large number, but I have never seen any actual numbers. I've looked through the AMR 10-K - nothing. Does anyone have an authoritative reference to such a number?

I did find something in the AMR 10-K which I thought was interesting. For some reason, I was always under the impression that airlines booked sales of FF miles at whatever the sell price was. Not so with AMR:

"Revenue earned from selling AAdvantage miles... is recognized in two components. The first component represents the revenue for air transportation sold and is valued at current market rates. This revenue is deferred and recognized over the period the mileage is expected to be used, which is currently estimated to be 28 months. The second revenue component, representing the marketing products sold, and administrative costs associated with operating the AAdvantage program, is recognized immediately."

Can anyone put this into plain English?

I would also like to see the Economist link.