That is user adjustable, that is the factor it uses in the estimation for consumption based on know or estimated speed limits on to you destination. If you typically drive faster than the posted speed limit you can adjust it up, drive slower adjust it down.
This is from their web site:
Reference speed Speed factor relative to the speed limits or estimated speed of the road.
Edit: I just tested on a 120 mile trip, at 100% estimated time 1:54, at 110% estimated time 1:44. At 100% would arrive with 26% left based on current state of charge, at 110% arrive at 22% left.
I’ve never adjusted - it was just showing in the live data from the integration with ABRP. Will have to keep an eye on it and see if it changes again at some point
IMHO. It is a speed you drive compared to posted speed. The problem that free version of ABRP calculate this based on just few recent drives. Paid version seems to have a whole history (that what they claim, never checked myself). Any live data stats is like this, unfortunately.