Normalized curves showing the number of stable orbits for different values of a_B and e_B. The sudden step in the number of cases marked the onset of a significant stable zone for that binary parameters. The normalization is performed to the maximum number of stable cases. Since the models run at the same pace, we expect that f measures the size of the stable region which saturates when the rate at which new stable cases are found is constant (i.e. the binary configuration presents a large stable zone for two planets).