Incursion factor
Incursion factor was the measurement of alteration to the timeline after a temporal incursion. It was measured by 29th century Starfleet officers.

After Seven of Nine created several temporal incursions to prevent ex-Captain Braxton from destroying the , the crew of the timeship  needed someone to clean up the timeline by going back in time to the beginning and preventing the chain of events from occurring in the first place. As Seven couldn't make another jump via temporal transporter without damaging herself and risking temporal psychosis, Captain Kathryn Janeway was selected for the role. After beaming to 2372 before Braxton arrived on Voyager, Janeway successfully prevented him from planting a temporal disruptor on the ship. Back on the bridge of Relativity, Lieutenant Ducane noted an incursion factor of 0.0036, which was better than he expected. ()
Time travel
Measurements