Airport operational efficiency is measured through different measures, with On-Time Performance being the primary internationally accepted standard. On-Time Performance is measured by comparing the actual off-block time (when aircraft pushes back) against the airline schedule time for a departing flight. The measurement is done in accordance with the IATA (International Airlines Transport Association) universal standard benchmark which considers a 15 minute deviation from the scheduled time as an on-time departure. The On-Time Performance of the airlines is averaged for a specific airport to produce On-Time Performance for the airport. This is bench marked against a target which is agreed upon by the airport stakeholders.