At Future.Travel we see that changes or cancellations are in excess of 5% of our total bookings.

In an interesting correlation, it would appear that people who buy discount tickets on low-cost carriers are most likely to try to change that ticket or to cancel. This could possibly be due to the fact that the prices are so cheap that they don’t read the cancellation policies. They end up forfeiting the price paid when they cancel the booking. Second to that in many cases the cost of changing is more than the cost of a new ticket on an LCC. The airline wins twice.

In general Airlines make more profit on changes than they do on the actual air fare from the original ticket.