Is a half-staffed foresters lodge just as efficient per worker as a fully staffed one?

Updated:

The first experiment was flawed (though the numbers were correct) foresters were not working in full grown forest. This next experiment is done few years later in a fully developed forest. Again - each experiment starts from the same savegame. Each number is averaged of 4 runs.

Full circle
 4 workers: 261 logs/year | 65 logs/person/year
 2 workers: 135 logs/year | 67 logs/person/year
 1 worker:  75 logs/year  | 75 logs/person/year

Half circle*
 4 workers: 157 logs/year | 39 logs/person/year
 2 workers: 121 logs/yea  | 60 logs/person/year
 1 worker:  58 logs/year  | 58 logs/person/year

* - only half of the circle was available for forestry other half was filled with pastures and fields: