Sorry that this took so long to find.
 
Out of "Beekeeping"  by John Eckert and Frank Shaw (1960):
They reported a work by Farrar (1931) in comparing colony strength by
counting the average number of flights out of the colony each minute.
 
3 pound package                  15 bees flying per minute
5 pound package                  48.5 bees flying per minute
3.5 pound overwintered colony    64.5 bees flying per minute
7 pound overwintered colony     128.3 bees flying per minute
 
Hope this answers your question of hive population.
 
 
John van Horn
first year, two hives (1 package, 1 swarm), no honey yet :-{