What do you want to count? When I wanted to compare recovery with armour / without armor I killed the rest, casted long spell (e.g. Wizard Eye) registered spell time left, and countered actions, say 30 or 40, then hit Enter and see spell time remaining. Then subtract and divide. Do it three or four times - because you may mistake yourselves. Better to count in RT mode. Because in turn-base mode you easily can mistake a blow for "turn to next round" or vice versa. But please specify what did you want to count?