1. The information reported is obtained from Statistical Data on Civil Aviation of China 2005e2012.
2. There is a change of classification of complaints by the CAAC starting in 2009. Therefore, the types of complaints are different from the previous years.
3. Over-sold tickets are likely to happen especially during high season and cause customers who cannot board their flights on time. Animal death are cases that animal died
during the transportation in aircraft. Re-funding are problems associated in the process of re-funding due to ticket changes or cancellation.