No idea on the average, but they can go all through the winter, on occasions.
Suggesion: You could mark a whole lot of therm from one colony, check numbers in the colony each day (at the same sort of time, and not mid afternoon), several colours for different batches might be good to confirm results as reliable (for your particular set of circumstances). You would also need to check your other hives for drifters, to assess non-lethal losses.
Repeat this at enough different times and you might get a reasonable estimate. Good luck. Oh and it could be skewed by how many actually mate.