The calendar year the figures cover.

The month the figures cover, as a number from 1 to 12.

The month the figures cover, as a three-letter abbreviation such as JAN.

The day the flights entered the airspace being measured.

The name of the airspace entity, such as an ANSP, a functional airspace block or a whole area like the SES area.

What kind of entity the row is, and whether its airspace is defined by ANSP areas of responsibility (AUA) or by flight information regions (FIR).

Which trajectory the distances come from. CPF is the flown trajectory from radar data, FTFM is the last filed flight plan, and SFR is the shortest constrained route.

The total length of the trajectories within the entity's airspace, in kilometres.

The total great circle distance between the points where flights entered and left the entity's airspace, in kilometres.

The total achieved distance, in kilometres. Each flight contributes its share of the great circle distance between its origin and destination. Comparing flown with achieved distance gives horizontal flight efficiency.