Equal Distribution not so equal?

I have calendly set to round robin and also equal distribution for my 2 closers. The setting team has booked 10 closing calls this week and 7 of them have gone to 1 closer and 3 to the other. 

I read that with equal distribution on it will optimise to no more than 3 more per person - but what it doesnt tell us is over what timeline? is this weekly/monthly or somethign else? 

Is there a way to set this myself to weekly? 

The guide is minimal on context in and around equal distrbution settings so would appreciate some help here. 

Thanks